Jan 31, 2007 9:00 PM EST

Mets pitcher Dave Williams had surgery Wednesday to repair a herniated disk in his neck and it's unclear how long he could be sidelined.

The team also announced that it agreed to a minor league contract with outfielder Ruben Sierra and invited him to spring training, and right-hander Jason Standridge chose to become a free agent after he was designated for assignment last week.

Via AP