Updated

Pittsburgh, PA (SportsNetwork.com) - The Pittsburgh Penguins agreed to a one- year contract with defenseman Christian Ehrhoff at the start of NHL free agency on Tuesday.

Ehrhoff and the Penguins agreed to a deal worth $4 million. Pittsburgh also signed goaltender Thomas Greiss and forward Blake Comeau to one-year contracts on Tuesday and re-signed forward Marcel Goc.

Ehrhoff, 31, became an unrestricted free agent recently after Buffalo used a compliance buyout to end his tenure with the Sabres. The German had seven years remaining on a 10-year, $40 million contract.

Ehrhoff posted 16 goals and 71 assists in 192 games with the Sabres. Over 692 career games with Buffalo, San Jose and Vancouver, the veteran blueliner has posted 313 points on 69 goals and 244 assists.

Greiss, 28, was signed for $1 million and will likely serve as the backup to No. 1 netminder Marc-Andre Fleury. The German backstop played for the Coyotes in 2013-14 and went 10-8-5 with a 2.29 goals-against average and .920 save percentage. In 69 career NHL outings, Greiss has compiled a 27-24-8 record along with a 2.43 GAA.

Comeau agreed to a $700,00 deal with Pittsburgh after recording five goals and 11 assists in 61 games with Columbus last season. The 28-year-old has 164 points (72G, 92A) over 422 career games with Calgary, Columbus and the New York Islanders.

Goc, 30, signed a $1.2 million deal. He was acquired from Florida at the trade deadline and had two assists in 12 regular-season games for the Penguins, missing the last nine with a lower-body injury. He also sat out the first four playoff games before leading the team in faceoff percentage over the last nine.