Cowboys defensive end Anthony Spencer, franchise-tagged for the second-straight season this year, will miss up to a month of training camp after he undergoes surgery on his left knee this week, coach Jason Garrett confirmed to reporters Tuesday.
Considering this news comes soon after it was revealed that defensive end Tyrone Crawford, who was scheduled to back up Spencer this season and was being thought of as a potential replacement for Spencer after this season, suffered a season-ending torn Achilles tendon, that's not good news for the Cowboys defensive line.
Also, defensive tackle Jay Ratliff injured his hamstring in a conditioning test, and he's out for the time being.
Spencer -- who is moving from outside linebacker to defensive end in the team's new 4-3 defensive scheme -- reportedly aggravated a bone bruise in his knee during Saturday's conditioning test. The injury goes back to OTA workouts this past offseason, and Spencer sat out mini-camp in order to rest the knee.
He is expected to be back in time for Week 1 of the regular season.