When the Ravens' offense broke the huddle during this week's organized team activities, one of the biggest changes was the first player to touch the football on each play.

The Ravens added Jeremy Zuttah as their new starting center in March, trading a 2015 fifth-round draft pick to the Tampa Bay Buccaneers in exchange for him. They signed Zuttah to a five-year, $18 million contract that includes $6.5 million guaranteed with a $3.5 million signing bonus.

So far, the Ravens are happy with their investment.

"Jeremy Zuttah is doing a great job," Ravens coach John Harbaugh said. "He's smart, really smart, really mature, goes about his business in a mature way. I'm just very impressed with how smart he is.

"He's very quick. He's about 305, 306 pounds. He looks good physically in there, but he can move. So, we'll see. It's going to be interesting to watch him play to see if he can prove himself."

Zuttah -- who replaces Gino Gradkowski as the Ravens' starting center -- Zuttah didn't allow a sack last season for the Buccaneers. The 6-foot-4, 308-pounder was the 22nd-ranked center last year, according to Pro Football Focus.

"Toughness," Zuttah said when asked what he'll add to the offense. "I've played a lot of games, experience. Athleticism, I don't think there are as many centers as athletic as I am."

The key for Zuttah, 27, is assimilating to offensive coordinator Gary Kubiak's schemes.