Maybe Capitals general manager George McPhee thinks the Boston Bruins want to exact revenge for their first-round playoff exit last spring.

Maybe coach Adam Oates thinks Tom Poti is too frail to handle the relentless forecheck of the Bruins’ power forwards.

Or maybe the Caps simply want toughness at both ends of the ice.

Whatever their reasons, four days after claiming enforcer Aaron Volpatti off waivers, the Caps signed defenseman Steven Oleksy to a one-year contract and recalled him from the Hershey Bears of the American Hockey League. To make room for Oleksy the Caps are expected to place defenseman Mike Green [groin] on injured reserve.

Olesky will wear No. 61 and will join the Cap at their morning skate on Tuesday at Kettler Capitals Iceplex. He is expected to be in the lineup Tuesday night against the Bruins, possibly in place of Poti, although the Caps could go with seven defensemen.

Oleksy, 27, has two goals, 12 assists and 151 penalty minutes in 55 games with Hershey this season. He currently leads the Bears and ranks third among AHL defensemen in penalty minutes.

At 6-foot, 190 pounds, Olesky is a right-shooting defenseman from Chesterfield, Mich., who was originally signed by Hershey on July 2, 2012.