The Pittsburgh Pirates lost a tough one in extra innings on Friday night, but the news got worse on Saturday. Catcher Francisco Cervelli had to undergo surgery due to a broken hamate bone in his left hand and will now have four to six weeks without baseball activity. In related matters, the Pirates have announced that they acquired catcher Erik Kratz from the Angels in exchange for cash considerations.

Cervelli injured his hand on a swing (MLB.com video here) in the fourth inning and had to leave the game.

Cervelli injured his hand on a swing. USATSI

Cervelli is a quality defensive catcher who gets on base well, as he has a .373 on-base percentage this season thanks in part to 30 walks against 35 strikeouts. He's actually been an underrated contributor these past two seasons for the Pirates.

Keep in mind, the timetable the Pirates gave was for a return to baseball activities, not necessarily the active big-league roster. Six weeks is reasonable, though. Pablo Sandoval had the same issue in 2011 and 2012 (one in each hand) and missed around six weeks both times.

With Cervelli down, Kratz will join Chris Stewart in handling the Pirates pitching staff. Offense will be hard to come by here, as Stewart is hitting .212/.325/.303 and Kratz is only 2 for 29 (.069) so far this year. Offense is secondary at catcher, though, and these two vets should be fine with the Pittsburgh pitchers.