Wilson Ramos
The Nationals may have lost another key player in Saturday's victory over the Reds, as catcher Wilson Ramos had to be helped off the field after twisting his right knee chasing a passed ball.

Ramos had an MRI on Saturday night and the team says it doesn't know the extent of the injury -- but their plans of calling up a catcher for Sunday's game shows they believe it could be a serious injury.

"Losing Willy is a big, big blow," Nationals manager Davey Johnson told reporters after the game (via the Washington Post). "I don't know how bad it is. I have a bad feeling he tore something in there and it's going to be a while. Just keep our fingers crossed. But right now, it's not good at all."

Jesus Flores will take over the primary catching duties in Ramos' absence, while Carlos Madonado is likely to be called up from Triple-A Syracuse on Sunday. Ramos is hitting .265/.354/.398 with three home runs.

The Nationals haven't played with their entire projected starting lineup all season. Neither outfielder Michael Morse nor closer Drew Stanton have yet to play this season, while Ryan Zimmerman, Jayson Worth, Rick Ankiel, Mark DeRosa, Chien-Ming Wang and Brad Lidge have all spent time on the disabled list.

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