Djokovic, the world No. 1, topped fifth-seeded Tomas Berdych 6-2, 7-6 (8-6) and Murray, seeded third, beat seventh-seeded Jo-Wilfried Tsonga 6-2, 7-6 (7-3) as Group A completed round-robin play.
Djokovic won the group with a 3-0 record and Murray was 2-1. Berdych was 1-2 and Tsonga, who played in the tournament finals last year, was 0-3.
The semifinal opponents will be determined in Saturday's final Group B matches.
The other group match sends 1-1 David Ferrer against 0-2 Janko Tipsarevic.
Djokovic sailed through the first set in 34 minutes Friday, winning three-quarters of the points on serve and posting breaks in the third and fifth games. He was up a break in the second set but Berdych broke back and forced a tiebreaker.
Berdych took the first three points and led 6-3 but Djokovic used a service winner to start a 5-0 run that he capped with another winner off serve.
Murray won the first four games versus Tsonga, taking more than 70 percent of the points on serve in the first set. Like Djokovic, Murray was up an early break in the second set but Tsonga claimed his only break of the match to pull even at 4-4. Murray controlled the tiebreaker, winning 6-of-7 points for a 6-2 lead.
Video of Victoria’s Secret models trying to 'twerk' hits Instagram
Costly malfunction causes beer flood at Boston-area brewery