(Reuters) - The San Antonio Spurs took to the court without three of their top scorers to face Chicago on Monday but still had too much fire power for the Bulls, pulling out a 103-89 victory to pick up their 13th win in 14 games.

Tony Parker (knee), Tim Duncan (knee) and Manu Ginobili (hamstring) all sat out for San Antonio, who own the best record in the NBA at 41-12, but a career-best 26 points from Kawhi Leonard and 18 from Danny Green kept the Spurs machine rolling.

"All of us are basketball players here, we're competitive," Leonard told reporters of the Spurs, who were also without Stephen Jackson for personal reasons.

"That's why we play the game. If we go in doubting ourselves, we're already beat."

San Antonio clung to a 76-75 lead in the fourth quarter before a 19-5 run closed the door on Chicago.

"One would hope you could play with anybody in our system, but it was a tough challenge tonight," said San Antonio coach Gregg Popovich. "I couldn't be more proud of them."

Nate Robinson scored 20 points to pace the Bulls while Joakim Noah added seven and 15 rebounds for the home team, who faded down the stretch.

The Bulls had dominated inside and outrebounded the visitors 49-26 but it did not seem to matter.

San Antonio grabbed a nine-point advantage at halftime and stretched it to 14 in the third before the Bulls closed the quarter strongly to make a game of it.

Chicago (30-21) have now lost three of four.

(Reporting by Jahmal Corner in Los Angeles, Editing by Peter Rutherford)