Mariners' George Kirby: Throws off mound, May return likely

Mariners general manager Justin Hollander said Monday that Kirby (shoulder) "felt great" while throwing a bullpen session over the weekend, Daniel Kramer of MLB.com reports.

Kirby is set to throw two more bullpen sessions this week before beginning a game progression. While Hollander wouldn't divulge a timetable for when the right-hander will be ready for his season debut, signs are pointing to it being sometime in May. Kirby was diagnosed with right shoulder inflammation back on March 7 but has made steady progress since then.