Baltimore Ravens quarterback Joe Flacco isn't pulling any punches when it comes to his offseason training regimen this year.

Flacco has taken up boxing at a Philadelphia gym to help improve his hand-eye coordination, strength and balance. Before you cue up the "Rocky" theme music, Flacco is throwing the punches and not taking them in his workouts.

For about an hour, Flacco puts on the gloves and delivers combinations into his trainer's padded gloves. He'll then punch on a heavy bag before doing an abdominal exercise for an hour.

So, is Flacco an "elite" boxer?

"He punches real hard," trainer Maleek Jackson told Baltimore's Press Box. "I think my arm was sore for like three hours."

Flacco isn't the only NFL quarterback who has added boxing to his workouts. The Seahawks' Russell Wilson recently posted a video of his work in the ring.

This is a much different offseason for Flacco than a year ago, when he spent his days rehabbing a surgically repaired left knee at the Ravens training facility. He never appeared to be fully recovered throughout last season, when he threw a career-high 4,317 yards but averaged 6.4 yards per attempt (27th in the NFL).

This offseason, Flacco's father recommended that the quarterback try boxing. Jackson, Flacco's trainer, has worked with Temple men's basketball team and Philadelphia Flyers players.

These boxing workouts are intended to help hand-eye coordination when throwing the ball on the move and his balance when moving side to side.

"It's the type of agility you need to perform in that type of sport and the same thing that boxing offers," Jackson said.