The deal keeps Holzer under contract with the NHL club through 2014-15 season. Financial details weren't immediately available.
The 25-year-old Holzer has appeared in 16 games with Toronto this season, registering two goals and 19 penalty minutes. The six-foot-three, 205-pound Holzer is tied for third on the team in blocked shots with 37.
A native of Munich, Holzer has represented Germany internationally, including at the 2010 Olympic Winter Games in Vancouver.
Toronto selected Holzer in the fourth round, 111th overall, in the 2006 NHL entry draft.
Life's about opportunity and how you respond to that opportunity, and obviously he must have some swagger about him, some confidence about him, because he was solid. He made some good saves. He was 6-foot-3 on every shot, which is a good thing for a goalie. He played well. We got a win.
— Maple Leafs coach Mike Babcock on rookie goaltender Garret Sparks, who made 24 saves in his first NHL start, a 3-0 win vs. Oilers
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