How low can Seattle go?

SEATTLE — Tony Parker set the tone with 10 of his 18 points in the first quarter, Manu Ginobili hit five 3-pointers and scored 19 off the bench, and the San Antonio Spurs were never challenged in an 120-79 win over the Seattle SuperSonics on Sunday night.

San Antonio won its third straight and for the 16th time in its past 18, and routed Seattle for the third time this season. The Spurs beat the Sonics by 20 in November and by 31 last month in San Antonio.

Tim Duncan scored 16 points and grabbed 10 rebounds, spending most of the second half as a spectator on the bench as San Antonio handed Seattle one of its worst home losses in franchise history.

The 41-point margin of defeat was Seattle’s biggest home loss since a 44-point setback to Dallas in 1985. Seattle’s worst home loss was a 47-point loss to Boston in 1968.

Seattle never led and looked ready for the offseason to arrive, especially after receiving word earlier Sunday that All-Star guard Ray Allen will miss the rest of the season after deciding he will have surgery on his injured left ankle.

Without Allen and his 26.4 points, Seattle’s offense had little potency from the perimeter. Luke Ridnour led Seattle with 16 points, but mostly scored on drives to the basket. Seattle, shooting 35.4 percent on 3-pointers this season, made just 3 of 12 3s.

The game became sloppy and reserved for seldom-used bench players in the fourth quarter. Seattle even used rugged forward Danny Fortson, who received a standing ovation when he checked in for the first time since Jan. 5, and promptly picked up a foul after just 44 seconds.

Not surprisingly, San Antonio coach Gregg Popovich immediately pulled Ginobili, Duncan and Parker.

Seven Spurs finished in double figures, with Jacque Vaughn adding 13, Matt Bonner scoring 12, and Michael Finley and Bruce Bowen both having 10.