The New York Islanders added defensieman Matt Carkner and center Brad Boyes through the free-agent market Sunday. Carkner reached an agreement with the Islanders on a three-year, $4.5 million contract after it appeared the Colorado Avalanche had announced they’d signed the 6-foot-4, 229-pounder. He had a goal, two assists and 33 penalty minutes in 29 regular-season games and added an assist and 21 penalty minutes in the playoffs for the Ottawa Senators this year. "We're very happy to add Matt to our defensive core for the next three seasons," Islanders general manager Garth Snow told NHL.com. "He brings good size and toughness to our blue line.” Boyes, 30, signed a one-year deal for $1 million. The former first-round pick of the Toronto Maple Leafs had eight goals and 15 assists in 65 games last season for the Buffalo Sabres. Injuries have plagued Boyes, a 43-goal scorer for the St. Louis Blues in 2007-08, the past few seasons.