Toronto sent John-Michael Liles and the rights to prospect Dennis Robertson to the Carolina Hurricanes for Gleason. The move comes one day after the club signed captain Dion Phaneuf to a seven-year extension.
"If you look at what our team looks like and maybe what we've lacked at times this year, it's been that ability to box people out. Penalty killing at times has not been as strong as it needs to be, and those are two areas that Tim is very good at," Toronto general manager Dave Nonis said. "It changes the look of our back end a little bit and gives (coach) Randy (Carlyle) some more options in terms of pairings."
Gleason, 30, is in his 10th NHL season, the last eight of which have been spent in Carolina. The 6-foot, 217-pound defender has one assist and a minus-7 rating in 17 games this season. He did not play in the team's last game, a 5-4 overtime win against the Montreal Canadiens, on Tuesday night. Gleason was a member of the 2010 United States Olympic team, going plus-3 in six games.
In his career, Gleason has 15 goals and 128 points in 616 regular-season games.
Liles, 33, has played in six games with the Leafs this year without registering a point. He had 11 points last season in 32 games. For his career, he has 77 goals and 313 points in 627 games.
Robertson, 22, is a senior defenseman at Brown University. He was drafted in the sixth round of the 2011 NHL Draft.