Little-used Sean Marks had 16 points and 13 rebounds, and Phoenix beat the Portland Trail Blazers 100-91 on Wednesday night in a game that ended up having no bearing on the Suns' playoff seeding.

San Antonio's rout of Utah earlier in the night locked Phoenix (55-27) into the sixth seed in the Western Conference. The Suns will open on the road against the No. 3 Spurs.

As the night began, the Suns had hoped to move up in the jumbled playoff race. They had only one shot at opening the playoffs at home: a victory coupled with a Houston loss to the Los Angeles Clippers. That scenario went by the boards when the Rockets blew out the Clippers.

Suddenly, the only out-of-town score that mattered was Utah at San Antonio, with a Spurs victory locking the Suns into the sixth slot.

Before the game, Phoenix coach Mike D'Antoni said he would monitor the San Antonio game and would pull his starters if it became clear that the Suns couldn't move up. Noting that he didn't want to risk an injury to a starter, D'Antoni said. "I'm not going to push fate."

The Spurs led Utah by 26 at halftime, and it wasn't long before D'Antoni sent in reserves D.J. Strawberry, followed by Marks, Alando Tucker and Eric Piatkowski.

Marks' 16 points matched a career high and his 13 rebounds set a career high.

Steve Nash, Amare Stoudemire and Shaquille O'Neal didn't play after halftime. Stoudemire finished with 12 points in 18 minutes, snapping his streak of consecutive 20-point games at 18 games, the third-longest in franchise history.

The Suns were already looking ahead to a playoff matchup against the Spurs, their longtime nemesis.

San Antonio has eliminated Phoenix in three of its last four postseason appearances. Last year's six-game defeat, in the second round, still galls Suns faithful.

The Suns were on their way to a dramatic Game 4 victory in San Antonio when Robert Horry sent Nash flying into the scorer's table. During the ensuing skirmish, Stoudemire and Boris Diaw left the bench, drawing one-game suspensions. Horry, a reserve, was suspended for two games.

The Spurs won Game 5 in Phoenix and closed out the series at home.

The Suns were involved in a lesser skirmish against Portland on Wednesday night.

Emotions boiled over late in the first half, when Portland's Jarrett Jack and Phoenix's Brian Skinner squared off at halfcourt. The players were quickly separated, but both were assessed double technical fouls and ejected.

Before play resumed, referee Steve Javie came to the scorer's table and asked to see a courtside monitor. After reviewing the play, he said the ruling stood.

The Suns didn't need Skinner to finish off the Blazers, who hit only one of their first 10 shots.

Travis Outlaw scored 24 points and had 12 rebounds for Portland, which finished 41-41 and missed a chance for its first winning record since 2002-03.

Notes:@ Phoenix forward Grant Hill was out with a groin injury. He's expected to be ready for the playoffs. Leandro Barbosa started in Hill's place. ... Portland's last victory in Phoenix came on Feb. 4, 2004. The Trail Blazers have dropped seven straight games in the desert since then and nine overall to Phoenix.

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