Updated

WASHINGTON (AP) Nationals pitcher Stephen Strasburg refuses to blame a benign growth he had removed from his back for problems he had last season.

Strasburg said Saturday at his team's fan festival that he had a fibrolipoma removed, adding ''it was above the muscle, so they didn't cut into muscle or anything.''

He said the procedure took about 15 minutes and he was told there is ''almost a zero percent chance'' the growth will return.

''I'm not going to say that it was the reason for pitching poorly or anything,'' Strasburg said.

Last month, Strasburg's agent, Scott Boras, disclosed that the pitcher had surgery to remove a non-cancerous growth from his back. Boras said Strasburg was bothered by the growth when he pitched.

Strasburg was 11-7 with a career-high 3.46 ERA in 2015. He spent time on the disabled list in May and June because of neck tightness, and in July and August because of a strained side muscle.

The right-hander can become a free agent after next season.