WASHINGTON -- Nationals third baseman Ryan Zimmerman needed a second surgery on his left hand/wrist on Tuesday after feeling numbness on the tips of his fingers and noticing significant swelling on the hand. The news comes less than a week after Zimmerman had his hamate bone removed from the wrist.

A spokesman for the Nationals said that Zimmerman had a small hematoma, which was causing some compression in the wrist. The problem was fixed by Dr. Richard Barth, the same doctor who performed surgery on Zimmerman last week. Zimmerman is expected to be 100 percent in four to six weeks and be ready for Spring Training.

"We felt we should go and do it now instead of waiting. We are kind of being overcautious," Zimmerman said by phone on Tuesday night.

Zimmerman, 22, hurt the wrist while taking batting practice on Nov. 4. After getting examined, it was revealed that Zimmerman has a fracture of the hook of the hammate bone, a small bone in the wrist commonly fractured in baseball players.

Zimmerman said he started having wrist problems in 2005, when he was playing in the Arizona Fall League. He said that he left the league a few weeks early because of the wrist. Zimmerman continued to have some discomfort in the wrist during the next two years, but it wasn't enough to make him miss games. In fact, Zimmerman played in all 162 games in 2007, and he led the Nationals in RBIs the last two years.

Zimmerman, who is considered by many to be the face of the Nationals franchise, hit .266 with 24 home runs, 91 RBIs and 99 runs scored in '07.