Thursday night in the sixth inning of the Cardinals' eventual 8-1 loss to the Nationals, St. Louis shortstop Rafael Furcal made what should have been a routine throw to second base. But it wasn't routine at all, as afterward Furcal was rubbing his elbow and ultimately left the contest. From MLB.com's Jenifer Langosch, shortly after the game:

There was already some early speculation that Furcal might have damaged his ulnar collateral ligament, which, if damaged severely enough, could require Tommy John surgery to repair. Even if it's just a muscle strain, Furcal would likely be sidelined for several weeks while his club tries to make a push for the postseason.

Furcal later reported having felt a "pop" in his elbow earlier in the inning, when he made a throw from deep in the hole, in an unsuccessful attempt retire Ian Desmond at first base. He felt the same "pop" on a throw home, before that third throw finally knocked him out of the game.

Utility infielder Daniel Descalso took over for Furcal Thursday night, and figures to get most of the playing time at shortstop as the Cardinals fight for one of the two National League wild-card slots.