When point guard Kemba Walker signed with the Celtics last summer, he told his mother that after eight years of sometimes quiet home games in Charlotte, her cheers would have a lot more company. He had seen the rowdy TD Garden crowds and he could not wait to have them on his side.
In the Celtics’ home opener Oct. 25, Walker helped Boston to a win over the Raptors, and he said the jolt was clear.
“It was incredible,” he said then. “It was everything I imagined. Best fans in the world, man. This fan base is no joke. They create the energy.”
Walker was most eager to see how the Garden rocked and rumbled during the playoffs, but TD Garden has sat empty for nearly three months now, and that will not change any time soon. No one knows exactly when professional sports will return after being shuttered because of COVID-19, or what they will look like when they do. But there is near-unanimous agreement that when the games do resume, there will be no fans there to watch them — not until this crisis is past.
In sports-crazed Boston, the absences figure to be more glaring than many other cities. The Patriots, Red Sox, Celtics, and Bruins routinely sell out their venues, and the supporters there routinely lose their voices. For a time, it appears, home-court and home-field advantages will be, well, silenced.
“I don't know what it's going to be like, because it's not something I've ever done,” Red Sox center fielder Jackie Bradley Jr. said. “It's unknown. It's uncharted territory.”
This situation, of course, is bad for the people who love munching on giant pretzels and roaring for their favorite players. But what does it mean for the players?
It will be jarring to see a Julian Edelman touchdown, a Jayson Tatum dunk, a Rafael Devers home run. or a David Pastrnak goal met with relative silence. But will their play change? Do the fans really affect their performance? Several experts say yes, but not necessarily because they get teams pumped up.
Tobias Moskowitz, an economist and Yale professor of finance, co-authored “Scorecasting: The Hidden Influences Behind How Sports Are Played and Games Are Won.” Among other topics, Moskowitz studied the influence home-court advantage has on a game’s outcomes. He looked at variables such as fan support, travel, and familiarity with venues.
“What we found was none of that really mattered,” Moskowitz said. “The main impact on the home-court advantage is really the fans’ impact on the referees. What you find is the referees kind of see things the home team’s way, especially on the really close calls that are hard to determine. It comes from psychology, the desire to relieve social pressure from people yelling at you.
“The obvious calls they don’t bias toward the home team. It’s really the ones where you could have called it either way, and so when 20,000 fans see it one way and you’re not sure what the right call is, it tends to influence your perspective.”
Moskowitz said the greatest impact from home-friendly officiating came in the basketball and soccer games he studied. Basketball games can be filled with a flood of whistles. Free throws, foul trouble, and block/charge calls can bump an equilibrium. Soccer has fewer calls, but their effects are more frequently severe. A penalty kick, or a red card the leaves a team a player down, can be crushing.
“Sure, baseball umpires call balls and strikes, but that’s only one-third of the time,” Moskowitz said. “Two-thirds of the time the batter swings, and most of the plays aren’t that close, so the impact on the game is relatively small.”
Kostas Pelechrinis, an associate professor at the School of Computing and Information at the University of Pittsburgh, said road teams can be negatively affected by travel, but also concluded that the fans’ effect on the officials appears to have the greatest consequences. Now, of course, that variable will likely be gone.
“I think it will be interesting,” said Pelechrinis, who has presented at MIT’s Sloan Sports Analytics Conference. “I expect it to reduce the impact of officiating. The officiating will be more fair, if we think it’s a little unfair now. But if, for example, the NBA puts everyone in a neutral setting, then you’re losing the traveling impact. So when you’re losing that and the referees’ [being swayed by fans], maybe it’ll be a more fair competition.”
Pelechrinis acknowledged there are no concrete ways to measure the psychological effects fans have on players. But players certainly gush about them quite often, if that can be considered an anecdotal metric.
Said Celtics assistant coach Jerome Allen, who also played in the NBA for two seasons: “Playing in front of fans is probably the ultimate competitive high for any professional athlete. I think if you asked any player how much attention they pay to the crowd and they told you none, I’d like to argue that they’re lying.”
But Allen added that pro athletes have unusual competitive fires. He said some of the most intense matchups take place in private workouts and pickup games, where the only witnesses are the players themselves.
“It doesn’t matter if the games are empty, when these guys play against their adversaries, they compete,” Allen said. "So I don’t think there will be a dropoff in their desire. I think the only noticeable dropoff is that others won’t be able to share in the experience.”
Brian Scalabrine, who played in the NBA for 11 seasons and now calls Celtics games for NBC Sports Boston, believes player performance is affected by crowds. He said some players are rattled by lively road environments, and some need the support that comes at home to truly thrive, especially in the playoffs. He said he has no idea how this new fan-less world might change things.
“This might sound a little crazy and be an overreach,” Scalabrine said, “but I think everything we know about what we’ve seen from teams this season, we could have to throw that out the window. We might have to reevaluate all teams based on how they play without fans.”
Scalabrine said that the Bucks, for example, thrive with a high-energy style that seems to feed off of crowds. Maybe they won’t have the same energy and zip now. There are no data points for this.
“There might be some insignificant player that’s all of the sudden just going to be the man, and we have no idea who that is,” Scalabrine said.
Regardless of the impact this odd setting has on players, there is no doubt that it’s all going to look and sound sort of weird. Teams might have to go to greater lengths to disguise play calls in the quiet environment, and television viewers might hear more in-game chatter on television.
When the Taiwan Baseball League restarted this month, there were mannequins and cardboard cutouts in the seats instead of people, and a five-man robot band played music. Don’t expect Bill Belichick to sign off on anything like that.
“Obviously, not having fans would be different,” Patriots fullback Danny Vitale said. “Do you throw in crowd noise, whatever it is? I don’t know.”
One company would like to try. Brad Roberts, who oversees international sales for the MyApplause app, said the company has already had discussions with several NBA teams about utilizing its software next season.
Currently, users can sign into a televised game and pick their allegiance, and when they tap certain buttons to cheer or boo or chant, the sounds are shared in real time with other fans who are logged in. Roberts said the hope is to make it a truly interactive platform that pipes the fan interactions into stadiums and arenas, both for players and television viewers to hear.
Moskowitz said he is eager to eventually have a new wealth of information to comb through after a sustained period of fan-less sporting events. Maybe the effects will be immense, or maybe they’ll hardly be noticeable.
“As a researcher, it gives us so much to look at, and I think the data will be interesting,” Moskowitz said. “But I’m a fan, first and foremost. I’d love to see us get back to normal.”
Julian McWilliams and Jim McBride of the Globe staff contributed to this report.
Note: The chart above has been updated to correct the data.