MIAMI -- One star returned to the game after an injury, the other did not -- and that was the difference.

Kawhi Leonard, playing with a bandage under his right eye, scored 27 points, including the final 12 of the game, as his San Antonio Spurs earned a 106-99 victory over the Miami Heat on Sunday night at AmericanAirlines Arena.

Leonard, who got accidentally scratched by Heat guard Tyler Johnson with 8:28 left in the fourth quarter, hit two mid-range jumpers and eight free throws to close out the win for the Spurs (4-0) over the Heat (1-2).

Despite the scratch, Leonard missed less than two minutes of game action.

"Having a guy like (Leonard), that when you are not getting anything out of your offense can take over, get fouled, get to the line and get easy points ... it helps," Spurs guard Manu Ginobili said.

Miami center Hassan Whiteside tied his career high with 27 points and added game highs in rebounds (15) and blocks (four). However, he left with 4:54 left in the fourth quarter due to cramps and did not return.

Whiteside, who played 35 minutes, was a team-high plus-7 while he was on the court. However, the team fell apart when he was absent, and that included Leonard's domination down the stretch.

Heat coach Erik Spoelstra, poised as usual, was obviously disappointed his team lost. But he also seemed pleased, looking at the big picture.

"I loved it," Spoelstra said. "I told (Whiteside), 'The reason you got the cramp was that was probably as hard as you've played at both ends of the court in a regular-season game.' That's what this team is going to need -- 34, 36 minutes of that every night."

Whiteside made 10 of 15 shots from the floor and 7 of 10 from the line. Heat point guard Goran Dragic scored 25 points on 9-of-17 shooting, including 3-of-7 on 3-pointers.

However, every other Heat player shot under 50 percent as the Spurs played their usual solid defense. Miami shot just 46.3 percent, including 38.5 percent in the first half, and Heat starting shooting guard Dion Waiters committed a game-high six turnovers while scoring only nine points.

Besides Leonard, the Spurs got 20 points and 11 rebounds from six-time All-Star center Pau Gasol, who is new to the team this year, replacing retired Tim Duncan in the post.

Backup point guard Patty Mills scored 18 points to lead a Spurs bench brigade that outplayed its Heat counterparts. Miami's four reserves all registered negative plus/minus numbers, with Johnson being the worst of the bunch at minus-16.

The Heat played poorly for most of the first half, falling behind by as many as 16 points in the second quarter.

"We need to take care of business so that they aren't able to build their lead so high," Dragic said of the first half, after which San Antonio led 52-44. "It's tough to try to catch them."

Miami cut its deficit to 77-72 after three quarters. The Heat shot 54.5 percent in the third quarter, finally awakening on offense.

The Heat, who hadn't led since 3-0 at the start of the game, pulled even for the first time at 79-79 with 10:23 left in the fourth quarter on a Justise Winslow bucket in the lane.

A basket by Dragic with 6:48 left in the fourth finally gave Miami the lead at 87-86.

But down the stretch, Leonard was too much for Miami, and the Spurs have now won six straight games in a rivalry that truly sparked when the teams split matchups in the 2013 and 2014 NBA Finals.

"He took over the game," Spurs forward David Lee said of Leonard. "That's what we expect of him, and he followed through as usual."

NOTES: The Spurs rested PF LaMarcus Aldridge, a five-time All-Star, as part of their customary plan to keep veteran players fresh. The Spurs rested PG Tony Parker and SG Manu Ginobili in their previous game, Saturday night against the New Orleans Pelicans. ... Spurs PF David Lee started in place of Aldridge and finished with eight points and 11 rebounds. Lee, 33, was a starter the first nine years in the league, but he started a combined total of just nine games the past two years. ... Willie Reed, Miami's 6-foot-10 backup center, is hoping to establish himself this year. He scored two points in 13 minutes Sunday. The 26-year-old has been released four times by NBA teams since he went undrafted out of Saint Louis University in 2011. ... Heat SF Justise Winslow is being used at point guard in certain situations. ... Miami's three-game homestand ends Tuesday against the Sacramento Kings. ... The Spurs return home to face the Utah Jazz on Tuesday.