In an unsurprising move, the Mariners added first baseman Dae-Ho Lee to their 40-man roster Sunday.
Lee, signed this offseason to compete for the backup first base job, had an opt-out clause in his contract that allowed him to become a free agent if he wasn't given the 40-man designation. That deadline was Sunday.
Reliever Justin De Fratus was reassigned to minor-league camp, leaving the Mariners with 36 players at big-league camp with the regular season a little more than a week away. General manager Jerry Dipoto announced the moves Sunday hours after optioning utility player Shawn O'Malley and right-hander Joe Wieland to Triple-A Tacoma.