Bucks forward plagued by ailing right ankle
He had missed the last 10 games with tendinitis in the ankle and will be out at least two more weeks, general manger Larry Harris said.
Van Horn has averaged 17.2 points and 8.2 rebounds in 13 games this season. He is Milwaukee's third-leading scorer and top rebounder.
Mercer played in the first three games of the season before injuring his left knee. He underwent successful arthroscopic surgery on Nov. 15, 2004, and is undergoing rehab. He has averaged 13.9 points in his career.
Moiso has previously played with Boston, New Orleans and Toronto. He has averaged 2.8 points and 2.9 rebounds in 133 games in the NBA.
The 7-foot-1, 240-pound Stepania played in one preseason game, scoring 11 points and grabbing seven rebounds in 15 minutes against Toronto. He was placed on the injured list on Nov. 1.
Stepania averaged 2.6 points and three rebounds in 42 games with the Blazers last season after being signed as a free agent.
Copyright 2004 by The Associated Press
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