Boston, MA (SportsNetwork.com) - Danny Green had 18 points and the San Antonio Spurs used a strong second half to beat the Boston Celtics, 111-89, on Sunday.

Boris Diaw added 15 points and seven rebounds for the Spurs, who have won seven in a row. Tim Duncan tallied 14 points, eight boards and two blocks.

Aron Baynes and Kawhi Leonard finished with 13 and 12 points, respectively, for San Antonio, which outscored Boston by a 66-40 margin in the second half.

Spurs coach Gregg Popovich returned from a two-game absence following a minor medical procedure.

Jeff Green ended with 16 points for the Celtics, who have dropped four straight. Evan Turner and Avery Bradley donated 12 and 11 points, respectively.

"The Spurs play the right way all the time," said Boston coach Brad Stevens. "They do it for 48 minutes. They do it for 82 games."

Each team led by as much as nine in the first half, with the Celtics holding a 49-45 edge at the break.

A tight third quarter featured seven lead changes and three ties. With the score tied 69-69, San Antonio ended the frame on a 9-4 spurt.

Boston got within 80-77 early in the fourth, but the Spurs responded with a 19-3 run. Baynes tallied nine points during the surge, including a layup with 4:38 remaining to make it 99-80.

Game Notes

San Antonio has won six straight against Boston ... The Spurs started a four- game road trip ... Brandon Bass and Marcus Thornton each had 10 points for the Celtics ... The Spurs made 11-of-26 3-pointers.