BOSTON – It shouldn’t matter as much as it seems certain to matter Friday night, when the Kansas City Royals meet the Boston Red Sox at Fenway Park in the first ballgame in this city since Monday’s tragedy.

It’s only baseball.

But Royals reliever Bruce Chen was on the mound on Sept. 21, 2001, at Shea Stadium as the starting pitcher for the New York Mets in their first home game after the 9-11 attacks. He has an idea of what to expect.

“There will be a lot of emotions,” Chen said, “and fans will have mixed feelings. They won’t want to be there but they’ll also want to cheer for their team.

“The game is something that gives them hope and is something that helps them keep going. We’re all concerned about the security, but one of the things we’re doing is trying to help the city get back to a sense of normalcy.

“Right now all they see is bad, bad, bad. If you can go back to what you used to do, even for a short time it’s a small step but it helps.”

Details are still emerging from the bombings Monday near the finish line of the Boston Marathon, which serves as the centerpiece of the Patriots Day celebration.

Those festivities always include an early start at Fenway Park. The Red Sox had already pulled out a 3-2 walk-off victory over Tampa Bay when the explosions killed three and injured more than 170.

“It’s a cowardly act by the people who did it,” said reliever Tim Collins, who grew up in nearby Worcester, Mass. “I didn’t have family members there but a lot of people did. That’s going to be a tough time for them.”

The Royals are staying at the Westin Copley Place hotel, which is the command center for the investigation. Security is tight. It is tight throughout the city. It figures to be especially vigilant at Fenway.

“It’s definitely something you think about,” said catcher George Kottaras, who lived near the bomb scene in 2008-09 while with the Red Sox. “If it can happen once, it can happen again.”

The Royals are bracing themselves for who knows what. They arrived Wednesday night after a 1-0 victory at Atlanta, and had all of Thursday to immerse themselves in the tragic aftermath.

“It definitely hits you that we’re playing in the first game back in Boston,” outfielder Jeff Francoeur said. “I’m sure they’re going to do some pregame ceremonies and there won’t be a dry eye in the stadium.

“We’ve been talking about that, a bunch of the guys. Tim is right. It probably will be the safest place in America, but I think it will also be a sad place.”

Manager Ned Yost was a coach on the Atlanta team that faced Chen and the Mets on that night in 2001. He, too, has an idea of what to expect Friday and realizes there’s no way to prepare.

“It’s going to be a pretty emotional night,” he said. “How do you prepare for anything like that? How do you prepare for somebody lighting a bomb off when everybody is having a good time. You can’t.”

But Yost, like Chen, also knows what this weekend series can mean to a grieving community.

“It sounds stupid because you really don’t have much of an impact,” he said, “but you just go and be with the city. Baseball promotes healing for everybody. And don’t ask me how.

“It just makes you feel better if you can go to a baseball game. It’s America’s pastime and it just helps heal. I’m glad that we’ve got the opportunity to go in there and help that process.”

“They are used to watching the Red Sox play and they will get to do that again,” said Chen. “It will help to bring a sense of normalcy to the city. Are we afraid it could happen again? Yes, we’re a little afraid. Everyone is. But it’s important for us to play.”