The Bucks took a 2-1 lead in the best-of-seven first-round Eastern Conference playoff series.
DeRozan missed all eight of his shots from the floor and finished with eight points, while the Raptors shot just 33 percent from the floor and went 6-for-22 from beyond the arc.
Kyle Lowry and Delon Wright led Toronto with 13 points apiece.
The Bucks shot 52.7 percent from the floor (39 of 74) and 52.2 percent from long range (12 of 23). Greg Monroe (16 points), Michael Beasley (13 points), Thon Maker (11 points) and Matthew Dellavedova (10 points) joined Middleton and Antetokounmpo in double figures.
Toronto came out flat in the opening quarter. The Raptors shot 22 percent and were nearly outscored single-handedly by Antetokounmpo, who had 10 in the opening quarter including a pair of 3-pointers as the Bucks jumped out to a 32-12 lead.
They blew the game wide open in the second, using a 14-2 run to go up by 31 after Monroe's layup with 6:11 left in the half and went into the break, up 57-30.
The frustration became obvious for Toronto late in the half. Serge Ibaka was called for a technical when he spiked the ball following a goaltending call with 2:03 left in the half and he was whistled for an offensive foul in the closing seconds, giving him two for the game.
Toronto went 2-for-11 from distance in the half.
Milwaukee finally cooled off in the third, making only 6 of 14 shots, but the Raptors' offense couldn't shake out of its funk. Toronto went 6-for-19 from the floor, made 2 of 7 3-pointers and trailed by 32 to open the fourth.
The Raptors got no closer than 23 points the rest of the way.
NOTES: The Bucks have led the series twice through the first three contests after holding a series lead just twice over their previous seven playoff appearances. Milwaukee has not won a playoff series since knocking off Charlotte in the 2001 Eastern Conference semifinals. ... Toronto G DeMar DeRozan had scored at least 20 points in nine of his previous 11 playoff games. ... The Raptors led the league with a 23-18 road record this season. ... Toronto won three of four regular-season meetings against Milwaukee this season.