The Patriots' depth at runningback will be tested after news broke this afternoon that the team's leading rusher so far, Fred Taylor, has to have surgery on his right ankle and may miss the rest of the season. According to Chris Gasper on the Globe's Extra Points blog:Taylor sustained an eversion ankle sprain -- meaning he rolled his ankle to the outside -- on his final carry in the Patriots' 27-21 win over the Baltimore Ravens on Sunday. Taylor, who finished the game with sev...