(SportsNetwork.com) - The San Antonio Spurs are in the thick of it for a fifth consecutive Southwest Division title, but they'll need a victory Sunday at home against the Phoenix Suns to make it a reality.

The defending NBA champion Spurs are tied for first in the Southwest Division with the Memphis Grizzlies, just a half-game in front of the Houston Rockets. The Spurs and Grizzlies share second out west with the Los Angeles Clippers.

The Spurs have inched toward the No. 2 seed in the Western Conference thanks to a 10-game winning streak. San Antonio has taken eight straight in Alamo City.

San Antonio made progress in the Southwest standings thanks a recent sweep of a home-and-home series with the Houston Rockets. After a 110-98 home win on Wednesday, the Spurs went to Houston and left with a 104-103 victory.

Tim Duncan was his old MVP self on Friday. He posted 29 points and 10 rebounds, but it was his last-second block on James Harden that everyone will remember.

San Antonio led by one when Harden forced Manu Ginobili into a turnover, giving the ball back to Houston with 6.1 seconds to play. Harden isolated on Kawhi Leonard out of a timeout and drove with his dominant left hand, but Duncan was there to meet him at the rim.

He turned aside the layup, then secured the rebound as the clock expired.

Leonard had 18 points and nine rebounds, and Patty Mills made all four of his shots, including three 3-pointers, for 14 off the bench.

The Spurs are 20-3 in their last 23 as they are gaining momentum in a bid for a repeat. They close the season in New Orleans on Wednesday.

The Suns have been dreadful of late. They've lost three straight and eight of their last nine to fall out of postseason contention.

Phoenix fell to the New Orleans Pelicans, 90-75, on Friday for its fifth consecutive road loss. The Suns finish the season Tuesday at home versus the LA Clippers.

Against the Pelicans, Eric Bledsoe had 19 points and seven assists for the Suns. Markieff Morris scored 12 to go with 11 rebounds, while P.J. Tucker chipped in 12.

A layup from Anthony Davis early in the fourth and a jumper from Dante Cunningham opened a 76-62 lead with 8:44 remaining. The Suns never cut the deficit inside double digits.

"There were a lot of loose rebounds and loose balls that they got," Suns coach Jeff Hornacek said. "I know several of them that if we could of just got those, we'd be off to the races and then maybe we could cut the gap."

The Spurs are 2-1 this season against the Suns with the only loss coming in Phoenix.