The Baltimore Ravens have suffered another injury blow as tight end Ed Dickson was forced to limp out of practice with a hamstring problem.

Dickson was set to replace Dennis Pitta in the Ravens side after Pitta suffered a season-ending hip injury during pre-season training last week.

The severity of Dickson's hamstring injury is unclear at the moment, although Ravens coach John Harbaugh has played down concerns, insisting that he was withdrawn as a precaution.

"Ed Dickson, his hamstring grabbed a little bit, so we pulled him out for precautionary reasons. We'll take a look at it and see how it looks," Harbaugh told the Baltimore Sun.

Dickson was part of the Ravens side that won the Super Bowl last season.