LOS ANGELES — Everything had to go right.
Boston College football coach Steve Addazio knew his Eagles had to submit their best effort of the season in each phase of the game Saturday if they had any intention of taking Southern Cal into the fourth quarter and surviving their first road game of the year.
“Obviously disappointed in the outcome today,’’ said Addazio, who dissected all that went wrong for the Eagles in their first loss of the season, 35-7, to the USC Trojans before a Los Angeles Memorial Coliseum crowd of 62,066.
“Don’t think we played exceptionally well at all, [that] would be an understatement,’’ Addazio said. “On defense we gave up  yards. On offense we gained about 185 — whatever it was — and rushed the ball for about 100. We just didn’t do much on either side of the ball.’’
USC had its way with the Eagles, who have a week off before hosting Florida State in an Atlantic Coast Conference contest Sept. 28 at Alumni Stadium.
The Trojans, who last weekend took a 10-7 loss to Pac-12 foe Washington State that prompted boos in the Coliseum, did all they wanted in rolling up a 28-0 lead, scoring a touchdown in each quarter, before BC freshman running back Tyler Rouse scored on a 29-yard run with 10:40 left in the game.
“We got to halftime, 14-0, tried to get ourselves regrouped and get a drive going, but it didn’t really happen,’’ Addazio said. “We went for it on a fourth-and-inches call and didn’t get it and set ourselves up to fall behind by another score. So, collectively as a team, we didn’t play the way our team has to play.’’
BC’s blueprint called for some specific goals.
“We had to get off the field on defense and get good field position on offense, try to control the ball and get the thing in the fourth quarter,’’ Addazio said. “And that didn’t happen.’’
BC senior quarterback Chase Rettig, a native of Sierra Madre, was stymied in his homecoming. He was held to 83 yards on 11-for-24 passing, with a long gain of 19 yards to David Dudeck. USC’s tight man coverage made it difficult for Rettig to find his favorite receiver, senior Alex Amidon, who was held to a pair of catches for 23 yards. Amidon made an 18-yard grab that sustained BC’s six-play, 68-yard scoring drive capped by Rouse’s TD scamper.
“They did everything we thought they would do,’’ Rettig said. “They just played better than us today. That’s about it.’’
Rettig was upstaged by USC sophomore Cody Kessler, who was declared the starter for the remainder of the season by coach Lane Kiffin last week.
Kessler took the opportunity and ran with it, throwing for 237 yards and a pair of touchdowns on 15-for-17 passing. He completed 14 in a row after failing to connect with Marqise Lee (2 catches, 90 yards) on a deep ball on the first play of the game.
“The first two weeks — I’m not making excuses — but you can’t really take control and be that guy to lead when you’re sharing reps,’’ said Kessler, who was in a quarterback platoon with Max Wittek.
Kessler overcame an opening three-and-out to direct a 14-play, 86-yard scoring drive that lasted 7:44 and sapped BC’s overmatched and undermanned defense on an arid, 90-degree Southern California afternoon.
Kessler capped it when he stood in a fast-eroding pocket and made a jump toss to a wide-open Tre Madden in the right flat. Madden went in untouched for a 5-yard TD and a 7-0 lead with 1:38 left in the first quarter.
“They went on that long drive and we didn’t respond,’’ Addazio said. “And that’s when it turned a little bit.’’
The Trojans took full control in the second quarter, when Kessler connected with Lee on a quick out from the USC 20.
Lee demonstrated why he won the 2012 Biletnikoff Award as the nation’s best receiver when he turned upfield, made Manny Asprilla miss, and took off for an 80-yard touchdown that gave USC a 14-0 lead with 8:49 remaining before intermission.
BC averted disaster on its ensuing series when a blocked punt that was returned by Lee for a touchdown was nullified by a USC offside penalty.
In desperate need of a score before halftime, the Eagles’ next series got off to a roaring start when Andre Williams (17 carries, 38 yards) burst up the middle for a 13-yard gain. But the Trojans quickly forced another punt and took a 14-0 lead into the break. BC ended the first half with 63 total yards.
“We felt good going into halftime from the standpoint that we would regroup and come back out,’’ Addazio said. “But we really couldn’t get it going on offense, but we couldn’t stop ’em.’’
After the Eagles gambled and lost on a fourth-and-1 at the USC 46, the Trojans wasted little time making it 21-0 when Madden scored on a 30-yard run with 4:15 to go in the third.
Madden (16 carries, 102 yards) went over the 100-yard mark for the third game in a row. At one point in the third quarter he had more total yards than BC.
Justin Davis tallied on a serpentine 17-yard run through BC’s defense to make it 28-0 with 13:30 left in the game before Rouse put the Eagles on the board.
Wittek came off the bench and capped an 11-play, 75-yard march with a 3-yard keeper that punctuated the victory.
“We’re not turning it over, we’re not a big penalty team, so that’s still been consistent and that’s a positive,’’ Addazio said. “But coming on the road like this, I knew they were a very talented football team and I think you saw that. We needed to play better to be in this game in the fourth quarter, and we didn’t play well enough to do it.’’