Herman has surgery, season likely over

New England Patriots tight end Brad Herman underwent surgery to repair an Achilles injury and will likely miss the season, according to a league source.

The undrafted rookie from Iowa was carted off the field during warmups of the team's organized team activity on Thursday. The Patriots have yet to make a roster move, but if Herman is placed on injured reserve (after first clearing waivers), he will not count against the 90-man roster limit.

Herman was one of just three tight ends set to practice on Thursday, joining second-year converted defensive end Alex Silvestro and veteran Bo Scaife. The team was without Rob Gronkowski (ankle) and Daniel Fells (unknown) for all of its OTA sessions open to the media, while Aaron Hernandez also missed Thursday's practice.

NOTE: A previous version of this story stated that Herman would still count against the 90-man roster limit. He will not.