WALTHAM -- The NBA has gone mad recently with opponents trying to fight each other (or at least pretending to want to throw down).

The Houston Rockets snuck through a passageway to gain entrance to the Los Angeles Clippers locker room. Ben Simmons and Kyle Lowry set up a meeting in the hallway (which never ended up happening). Arron Afflalo took an ambitious swing at Nemanja Bjelica, which didn't really connect, but still.

NBA players have been an angry bunch lately. And Boston Celtics star Al Horford thinks the violent edge needs to stop.

"Very bizarre," Horford said of the recent incidents. "I don't think I can remember a period of time with all this chippiness going on. I think that you want to compete, you want to play hard. That's fine. But all that extra stuff, you know, it needs to stop. At the end of the day you need to focus on basketball. We're here to play. And I'm sure the NBA will address those things and fix them. We're professionals. We can't get caught up in that stuff."

Horford hardly ever gets into it with opponents.

"It's hard," he said. "But we have to remember what we play the game for. And I'm playing to win, I'm playing for my teammates. And sometimes you need to take a step back before you do something you regret. And that's the way that I look at it."