According to Matheny, Molina's knee began to bother him during the final innings of Friday's game. Molina was ruled unavailable to play on Saturday, though the club did not divulge that information until postgame. The knee that is bothering Molina now is the same one the catcher had operated on in Sept. 2007.
Molina, who has started 78 games as catcher, leads the National League with a .346 batting average. Tony Cruz started in Molina's place on Saturday and finished 1-for-4.
Jenifer Langosch is a reporter for MLB.com. Read her blog, By Gosh, It's Langosch, and follow her on Twitter @LangoschMLB. Chad Thornburg is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.