TAMPA, Fla. — When Aroldis Chapman stood at his locker in the Yankees’ spring training clubhouse last week, he was resolute in defending himself. He knew that Major League Baseball was investigating his actions in an October episode in which, according to a police report, he placed his hands around his girlfriend’s neck during an argument and fired a gun eight times. He knew he was in great danger of being suspended.

Still, he struck a defiant note.

“I’ve never hurt anybody, never in my life,” Chapman told reporters in Spanish, maintaining that he would fight any suspension that was imposed on him. “That’s not my character or who I am.”

But Chapman took a far different stance on Tuesday when he agreed to accept a 30-game suspension handed down by Commissioner Rob Manfred that will begin on opening day. It is the first suspension under baseball’s new domestic violence policy, which was written in concert with the players’ union and enacted last August.

Chapman, who will lose about $1.86 million from his 2016 salary of $11.3 million, is eligible to return to the Yankees on May 9. Until then, he can participate in spring training and play in the team’s exhibition games, which begin Wednesday. But once the regular season begins, Chapman, one of the game’s premier relievers and its hardest thrower, will be restricted to working out at the Yankees’ complex here. Whether he will be ready to pitch on May 9 remains to be seen.