Djokovic first took to the hard courts at Rexall Centre in the afternoon session and defeated American Sam Querrey 6-4, 6-4 in a match that was originally set for Thursday but pushed back by rain.
Then in the evening, the reigning Rogers Cup champion completed a 6-3, 3-6, 6-3 win over German Tommy Haas to reach the semifinals.
Also notching a pair of wins Friday was fifth-seeded Serb Janko Tipsarevic, who first bested No. 10 Marin Cilic of Croatia 6-2, 6-4, then reached the semis by downing Marcel Granollers by 6-4, 6-4.
Eighth-seeded American John Isner reached the quarters with a 6-7 (3-7), 6-4, 6-4 triumph over No. 12 seed Philipp Kohlschreiber, then moved on with a 7-6 (11-9), 6-4 decision over 16th-seeded Milos Raonic of Canada.
Also reaching the semis was Frenchman Richard Gasquet, who rallied from a set down to beat Mardy Fish of the United States 5-7, 6-1, 6-2 after first besting fourth-seeded Czech Tomas Berdych 6-4, 6-2.