The Chicago Blackhawks improved their depth at the start of the free-agency period Friday, signing veterans Andrew Brunette Jamal Mayers and Dan Carcillo to one-year contracts.Brunette, 37, is coming off an 18-goal, 28-assist season with the Minnesota Wild . The left wing has 256 goals and 450 assists in 1,032 career games with the Wild, Colorado Avalanche Nashville Predators and Washington Capitals Brunette played under Blackhawks coach Joel Quenneville for three seasons in Colorado.O'Donnell, 39, has played 16 NHL seasons with seven teams. The stay-at-home defenseman played 81 games with the Philadelphia Flyers last season, posting 1 goal and 17 assists.Mayers, 36, has played 13 NHL seasons with four teams. The right wing had 3 goals and 11 assists in 78 games with the San Jose Sharks last season while playing the role of fourth-line forward.Carcillo, 26, recorded 2 goals -- both game-winners -- and 6 points along with 127 penalty minutes in 57 regular-season games for the Flyers last season. He added 2 goals, 1 assist and 30 penalty minutes in 11 Stanley Cup Playoff games.The Blackhawks also signed 32-year-old Brett McLean , who had 10 goals and 17 assists in 50 games with Bern of the Swiss League, where he has spent the last two seasons. In 385 career regular-season games over parts of six NHL seasons with Chicago, Colorado Avalanche (2005-07) and Florida Panthers (2007-09), he had 56 goals and 106 assists.