A look at the track competitions of the London Olympic Games:
WORLD RECORD: 9.58, Usain Bolt, Jamaica (2009)
US ENTRIES: Ryan Bailey, Justin Gatlin, Tyson Gay
WHAT TO LOOK FOR: All eyes will turn to Jamaica in the marquee event. Usain Bolt is the defending gold medalist, but lost twice in 48 hours in Kingston, Jamaica, to countryman Yohan Blake, who owns the year’s best time, a 9.75 mark in June.
WORLD RECORD: 19.19, Usain Bolt, Jamaica (2009)
US ENTRIES: Maurice Mitchell, Wallace Spearmon, Isiah Young
WHAT TO LOOK FOR: Blake also beat Bolt in the 200 at the Jamaican Olympic Trials this year and the two enter as favorites, but look for Spearmon to shoot for redemption after getting disqualified in Beijing for stepping out of his line, taking away what would have been a bronze.
WORLD RECORD: 43.18, Michael Johnson, US (1999)
US ENTRIES: Tony McQuay, LaShawn Merritt, Bryshon Nellum
WHAT TO LOOK FOR: Merritt returns to defend his Beijing gold, and holds the year’s top time, but all eyes will likely be on South African Oscar Pistorius, who will become the first double amputee runner at the Games.
WORLD RECORD: 1:41.01, David Lekuta Rudisha, Kenya (2010)
US ENTRIES: Khadevis Robinson, Duane Solomon, Nick Symmonds
WHAT TO LOOK FOR: Two Kenyans medaled in Beijing, but a new guard has stepped forward for London. Lekuta Rudisha is the world record-holder and ran a 1:41.54 on June 7, over 2 seconds faster than the next best time this year.
WORLD RECORD: 3:26.00, Hicham El Guerrouij, Morroco (1998)
US ENTRIES: Matthew Centrowitz, Leonel Manzano, Andrew Wheating
WHAT TO LOOK FOR: Same story, different race for the Kenyans here. Asbel Kiprop is the defending gold medalist after Bahrain’s Rashid Ramzi was stripped of his title, but was beat out in May by countryman Silas Kiplagat for the year’s top time.
WORLD RECORD: 7:53.63, Saif Saaeed Shaheen, Qatar (2004)
US ENTRIES: Kyle Alcorn, Donn Cabral, Evan Jager
WHAT TO LOOK FOR: Kenyan Brimin Kiprop Kipruto is back to defend his gold, and will be challenged by a bevy of countrymen, who own the world’s top nine times this year.
WORLD RECORD: 12:37.35, Kenenisa Bekele, Ethiopia (2004)
US ENTRIES: Bernard Lagat, Lopez Lomong, Galen Rupp
WHAT TO LOOK FOR: Besieged by recent injuries, Beijing gold medalist Kenenisa Bekele looks to have returned to form, but the Ethiopian still has a long road to repeating. The world’s top 10 times were all run at Paris Saint-Denis in July, and all were by either Ethiopians or Kenyans.
WORLD RECORD: 26:17.53, Kenenisa Bekele, Ethiopia (2005)
US ENTRIES: Rupp, Dathan Ritzenhein, Matt Tegenkamp
WHAT TO LOOK FOR: Bekele also scored gold in this event in 2008, and will also have his hands full, with Kenyans Wilson Kiprop and Moses Ndiema Masai nipping at his heels.
WORLD RECORD: 12.87, Dayron Robles, Cuba (2008)
US ENTRIES: Aries Merritt, Jeff Porer, Jason Richardson
WHAT TO LOOK FOR: Americans David Payne and David Oliver both medaled in Beijing, but the path is paved for a new crop. Aries Merritt and Jason Richardson hold two of the world’s top three times this year, but look for 2004 gold medalist Liu Xiang to rebound after withdrawing in ‘08 with an Achilles injury that disappointed his home country.
WORLD RECORD: 46.78, Kevin Young, US (1992)
US ENTRIES: Kerron Clement, Angelo Taylor, Michael Tinsley
WHAT TO LOOK FOR: The United States had a podium sweep the last time around, including Taylor’s gold and Clement’s silver. The finals could be Great Britain’s most anticipated event; team captain Dai Greene is .06 seconds behind Puerto Rican Javier Culson for the year’s best time.
WORLD RECORD: 8 feet 1/2 inch, Javier Sotomayor, Cuba (1993)
US ENTRIES: Erik Kynard, Jamie Nieto, Jesse Williams
WHAT TO LOOK FOR: Beijing silver medalist Germaine Mason is gone, so the host’s hopes rest on Robert Grabarz, owner of the fifth-best jump this year. Russians Ivan Ukhov and Andrey Silnov (‘08 gold) will be the ones to beat.
WORLD RECORD: 29 feet, 4 1/2 inches, Mike Powell, US (1991)
US ENTRIES: Will Claye, Marquise Goodwin, George Kitchens
WHAT TO LOOK FOR: Great Britain’s Greg Rutherford is tied for the year’s highest jump with Russian Sergey Morgunov, and might be his country’s best chance for a gold in track and field.
WORLD RECORD: 60 feet 1/4 inch, Jonathan Edwards, Great Britain (1995)
US ENTRIES: Claye, Christian Taylor
WHAT TO LOOK FOR: No American medaled at Beijing, but Taylor and Claye have the top two marks in the world this year.
WORLD RECORD: 20 feet 1 1/4 inches, Sergey Bubka, Ukraine (1992)
US ENTRIES: Derek Miles, Jeremy Scott, Brad Walker
WHAT TO LOOK FOR: Since winning the Beijing gold, Great Britain’s Steve Hooker has continued a steady decline, one marked by injury, culminating in three failed attempts at the London Grand Prix. The door is open for France’s Renaud Lavillenie, among others.
WORLD RECORD: 323 feet, 1 inch, Jan Zelezny, Czech Republic (1996)
US ENTRIES: Sean Furey, Craig Kinsley, Cyrus Hostetler
WHAT TO LOOK FOR: The Czech Republic’s Vitezslav Vesely comfortably has the year’s top mark. Beijing gold medalist Andreas Thorkildsen of Norway is 13th on the list.
WORLD RECORD: 243 feet 1/2 inch, Jurgen Schult, East Germany (1986)
US ENTRIES: Lance Brooks, Jarred Rome, Jason Young
WHAT TO LOOK FOR: Lithuanian Virgilijus Alekna and Poland’s Piotr Malachowski each medaled in 2008 and are in the top five this year, but Germany’s Robert Harting, the 2012 Euro champion, holds the two best distances.
WORLD RECORD: 75 feet 10 inches, Randy Barnes, US (1990)
US ENTRIES: Christian Cantwell, Reese Hoffa, Ryan Whiting
WHAT TO LOOK FOR: Cantwell won silver in 2008, and has the year’s best mark, but right behind him is fellow American Reese Hoffa. Along with Whiting, the United States holds the six top distances this year.
WORLD RECORD: 284 feet 7 inches, Yuriy Sedykh, Soviet Union (1986)
US ENTRIES: Kibwe Johnson, A.G. Kruger
WHAT TO LOOK FOR: Belarus’s Ivan Tsikhan is poised to make the leap to gold after taking bronze four years ago.
4 x 100-meter relay
WORLD RECORD: 37.04, Jamaica (2011)
US ENTRIES: Bailey, Gatlin, Gay, Trell Kimmons, Doc Patton, Mike Rodgers
WHAT TO LOOK FOR: With Blake and Bolt at the helm, can the Jamaicans be stopped in their quest for repeat gold? Trinidad and Tobago won silver in Beijing, and should be their top challenger.
4 x 400-meter relay
WORLD RECORD: 2:54.29, US (1993)
US ENTRIES: Maurice Mitchell, Spearmon, Young, Ronnell Mance, Manteo Mitchell, Jeremy Wariner
WHAT TO LOOK FOR: United States teams hold the year’s top two marks, but none of the runners from Beijing’s gold-medal unit return.
WORLD RECORD: 2:03:38, Patrick Makau Musyoki, Kenya (2011)
US ENTRIES: Abdi Abdirahman, Ryan Hall, Meb Keflezighi
WHAT TO LOOK FOR: The top 33 times this year have been posted by runners hailing from either Ethiopia or Kenya. Ayele Abshero of Ethiopa leads the field with a 2:04:23 mark in Dubai this January.
20-kilometer race walk
WORLD RECORD: 1:17:16, Vladimir Kanaykin, Russia (2007)
US ENTRIES: Trevor Barron
WHAT TO LOOK FOR: Italy’s Alex Schwazer, the 2008 gold medalist in the 50-kilometer race walk, has the year’s best time, but a pair of Chinese race-walkers in Zhen Wang and Ding Chen could challenge his dominance.
50-kilometer race walk
WORLD RECORD: 3:34:14, Denis Kizhegorodov, Russia (2008)
US ENTRIES: John Nunn
WHAT TO LOOK FOR: Two Russians -- Sergey Kirdyapkin and Igor Erokhin -- are at the top of the year’s leaderboard, but look for Australian Jared Tallent to avenge his silver medal performance in the last Olympics.
WORLD RECORD: 9,039 points, Ashton Eaton, US (2012)
US ENTRIES: Ashton Eaton, Trey Hardee
WHAT TO LOOK FOR: Defending gold medalist Bryan Clay was bounced during the Olympic Trials, so bringing the top prize back to America is in Eaton’s hands after the 24-year-old set the world record earlier this year.
WORLD RECORD: 10.49, Florence Griffith-Joyner, US (1988)
US ENTRIES: Allyson Felix, Carmelita Jeter, Tianna Madison
WHAT TO LOOK FOR: Can the United States dethrone the Jamaicans after they swept the medal stand in Beijing? Gold medalist Shelly-Ann Fraser-Pryce owns the year’s top time, but Jeter and Felix are both in the top five.
WORLD RECORD: 21.34, Florence Griffith-Joyner, US (1988)
US ENTRIES: Felix, Jeter, Sanya Richards-Ross
WHAT TO LOOK FOR: Felix, Ross, and Jeter hold three of the year’s top four times, and Jamaica’s Veronica Campbell-Brown, the 2008 gold medalist, has had a down year.
WORLD RECORD: 47.60, Marita Koch, Germany (1957)
US ENTRIES: Richards-Ross, Francena McCorory, DeeDee Trotter
WHAT TO LOOK FOR: Great Britain’s Christine Ohuruogu, the defending gold medalist, had a disappointing 2011 that included a false start at the World Championships, but she is hitting her stride at the right time, and should be a crowd favorite in London.
WORLD RECORD: 1:53.28, Jarmila Kratochvilova, Czech Republic (1983)
US ENTRIES: Geena Gall, Alysia Montano, Alice Schmidt
WHAT TO LOOK FOR: Kenya’s Pamela Jelimo has the world’s top two times this year, and a Beijing gold around her neck.
WORLD RECORD: 3:50.46, Yunxia Qu, China (1993)
US ENTRIES: Shannon Rowbury, Jenny Simpson, Morgan Uceny
WHAT TO LOOK FOR: Morocco has never medaled in the women’s 1,500 meters. Might Mariem Alaoui Selsouli, owner of the world’s top 2012 time, be the first?
WORLD RECORD: 8:58.81, Gulnara Galkina, Russia (2008)
US ENTRIES: Emma Coburn, Bridget Franek, Shalaya Kipp
WHAT TO LOOK FOR: Russia took two medals in Beijing, including the gold from Galkina, but Yuliya Zaripova might be their best shot at reaching the podium this year; Galkina is not in the top 16 times this year.
WORLD RECORD: 14:11.15, Tirunesh Dibaba, Ethiopia (2008)
US ENTRIES: Kim Conley, Julie Culley, Molly Huddle
WHAT TO LOOK FOR: Ethiopa’s Meseret Defar won bronze four years ago, and has the world’s second-fastest time this year.
WORLD RECORD: 29:31.78, Junxia Wang, China (1993)
US ENTRIES: Janet Bawcom, Amy Hastings, Lisa Uhl
WHAT TO LOOK FOR: Tirunesh Dibaba swept the gold in the 5,000 and the 10,000 in Beijing, and looks poised to repeat in the 10,000, though Kenyan Florence Jebet Kiplagat is just .46 seconds behind her in 2012 times.
WORLD RECORD: 12.21, Yordanka Donkova, Bulgaria (1988)
US ENTRIES: Dawn Harper, Lolo Jones, Kellie Wells
WHAT TO LOOK FOR: Jones might steal the attention, but Harper is defending her Beijing gold medal and Australian Sally Pearson won silver and is back with the world’s best time this year.
WORLD RECORD: 52.32, Yuliya Pechenkina, Russia (2003)
US ENTRIES: T’erea Brown, Lashinda Demus, Georganna Moline
WHAT TO LOOK FOR: Great Britain’s Perri Shakes-Drayton will have to spoil a Russian party to take the gold. Natalya Antyukh and Irina Davydova are ranked first and second in 2012 times, respectively.
WORLD RECORD: 6 feet 10 1/4 inches, Stefka Kostadinova, Bulgaria (1987)
US ENTRIES: Amy Acuff, Brigetta Barrett, Chaunte Lowe
WHAT TO LOOK FOR: Former world champion and Beijing silver-medalist Blanka Vlasic recently withdrew due to injuries and various health issues, opening the door for Belgian Tia Hellebaut to defend her gold. Lowe and Barrett have two of the world’s top four times, and could be in line to medal.
WORLD RECORD: 24 feet 8 1/4 inches, Galina Chistyakova, Soviet Union (1988)
US ENTRIES: Janay Deloach, Chelsea Hayes, Brittney Reese
WHAT TO LOOK FOR: The United States was kept off the Beijing podium, but Reese’s July jump in Oregon is the world’s best, while Hayes has the fourth-best leap this yea.r
WORLD RECORD: 50 feet 10 1/4 inches, Inessa Kravets, Ukraine (1995)
US ENTRIES: Amanda Smock
WHAT TO LOOK FOR: Ukraine’s Olha Saladuha and Colombian Caterine Ibarguen are far and away the top contenders, at least based off their 2012 performances.
WORLD RECORD: 16 feet 7 1/4 inches, Yelena Isinbayeva, Russia (2009)
US ENTRIES: Becky Holliday, Lacy Janson, Jenn Suhr
WHAT TO LOOK FOR: Suhr won silver in Beijing, and her 2012 best is markedly better than any other in the world.
WORLD RECORD: 234 feet 2 inches, Barbora Spotakova, Czech Republic (2008)
US ENTRIES: Brittany Borman, Kara Patterson, Rachel Yurkovich
WHAT TO LOOK FOR: The Czech Republic’s Barbora Spotakova is in prime position to defend her Beijing gold, but South african Sunnette Viljoen got the best of her in June in New York.
WORLD RECORD: 252 feet, Gabriele Reinsch, East Germany (1988)
US ENTRIES: Stephanie Brown Trafton, Gia Lewis-Smallwood, Aretha Thurmond
WHAT TO LOOK FOR: American Stephanie Brown Trafton will defend her gold against, among others, a markedly improved Russian in Darya Pishchalnikova.
WORLD RECORD: 74 feet 3 inches, Natalya Lisovskaya, Soviet Union (1987)
US ENTRIES: Tia Brooks, Jill Camarena-Williams, Michelle Carter
WHAT TO LOOK FOR: It appears to be a two-horse race between New Zealand’s Valerie Adams and Belarus’s Nadzeya Ostapchuk, who won gold and bronze, respectively, in Beijing. The two have combined for the world’s top 10 distances this year.
WORLD RECORD: 260 feet 6 inches, Betty Heidler, Germany (2011)
US ENTRIES: Amanda Bingson, Amber Campbell, Jessica Cosby
WHAT TO LOOK FOR: Aksana Miankova of Belarus is the defending gold medalist, but she will have the world record-holder Heidler to deal with.
4 x 100-meter relay
WORLD RECORD: 41.37, East Germany (1985)
US ENTRIES: Felix, Jeter, Madison, Bianca Knight, Jeneba Tarmoh, Lauryn Williams
WHAT TO LOOK FOR: The United States has the world’s best time this year, but was left off the podium in Beijing, where Russia took top honors.
4 x 400-meter relay
WORLD RECORD: 3:15.17, Soviet Union (1988)
US ENTRIES: Richards-Ross, McCoroy, Trotter, Keisha Baker, Diamond Dixon
WHAT TO LOOK FOR: American Debbie Dunn recently withdrew from the relay pool after a positive drug test, but the United States is still loaded for another gold medal run.
WORLD RECORD: 2:15:25, Paula Radcliffe, Great Britain (2003)
US ENTRIES: Desiree Davila, Shalane Flanagan, Kara Goucher
WHAT TO LOOK FOR: Constantina Dita became the oldest Olympic marathon gold medalist in Beijing and will defend her title in London, but a bevy of Ethiopan and Kenyan runners look poised to dethrone her.
20-kilometer race walk
WORLD RECORD: 1:25:08, Vera Sokolova, Russia (2011)
US ENTRIES: Maria Michta
WHAT TO LOOK FOR: This is event has been dominated by the Russians and the Chinese this year. The two countries have combined for the world’s top 14 times, including leader Elmira Alembekova.
WORLD RECORD: 7,291 points, Jackie Joyner-Kersee, US (1988)
US ENTRIES: Sharon Day, Hyleas Fountain, Chantae McMillan
WHAT TO LOOK FOR: Fountain won silver in Beijing, but Great Britain’s Jessica Ennis has the world’s best score this year, and will challenge for a gold on home soil.
Alex Prewitt can be reached at email@example.com. Follow him on Twitter @alex_prewitt.