Pittsburgh Penguins lose defensemen Olli Maatta, Justin Schultz

The Pittsburgh Penguins are starting to get a bit thin along their blue line.

Pittsburgh announced Friday that defenseman Olli Maatta is expected to be sidelined six weeks after undergoing surgery on his hand.

The 22-year-old Finn injured his left hand after being crunched into the boards by Winnipeg forward Adam Lowry on Thursday in the Penguins' 4-3 overtime victory over the Jets.

Coach Mike Sullivan also told the Pittsburgh Post-Gazette that fellow blue-liner Justin Schultz has been diagnosed with a concussion after being hit by Jets defenseman Dustin Byfuglien, also on Thursday. The 26-year-old Schultz, who is the league's concussion protocol, is sitting out Friday's game against the Columbus Blue Jackets and is questionable to face the Detroit Red Wings on Sunday.

Pittsburgh addressed these absences prior to Friday's game by recalling defensemen Cameron Gaunce and Steve Oleksy from Wilkes-Barre/Scranton of the American Hockey League.

"They both have steady games," Sullivan told the Pittsburgh Post-Gazette of Guance and Oleksy. "They're strong kids. They're good in front of our net. They're strong underneath the hashmarks. They defend hard, and they have a steady simplicity to their game that I think helps us."

Maatta has recorded one goal, six assists and a plus-17 rating. He has 17 goals and 47 assists in 219 career contests -- all with the Penguins -- since being selected with the 22nd overall pick of the 2012 draft.

Schultz has collected nine goals and 30 assists and a plus-31 rating in 56 games. The 26-year-old is in the midst of his first full season with Pittsburgh after spending parts of four seasons with the Edmonton Oilers.

Guance, 26, notched a pair of assists and a plus-3 rating in three games with Pittsburgh earlier this season.

Oleksy, 31, has set up a goal and recorded 22 penalty minutes in nine NHL appearances.