Western Conference leaders FC Dallas secured their place in the MLS Cup playoffs with their 0-0 draw against the host Portland Timbers.
The draw pushed Dallas (15-6-9, 54 points) three points ahead of Sporting Kansas City, who play at home Sunday against Real Salt Lake. With a win, SKC would sit even on points, though they would hold the first tiebreaker with more victories overall.
Portland (13-9-9, 48 points) also moved back into sole possession of fourth place with the draw, after Seattle had pulled even with its victory over Colorado earlier Saturday.
But the Timbers finished the match without starting goalkeeper Jeff Attinella, who left the game a few minutes before full time with an apparent shoulder injury. And they will be without defender Liam Ridgewell for next Saturday's match at Real Salt Lake after he was sent off in second-half stoppage time for his challenge into the back of Roland Lamah.
The contest ended with Timbers coach Giovanni Savarese yelling at referee Allen Chapman and his officiating crew, with Dallas coach Oscar Pareja among those helping to restrain him.
In a first half with few chances, Dallas came closest to breaking through when Carlos Gruezo's deflected shot rattled the right post in the 44th minute.
Things were somewhat more lively after the break.
Diego Valeri carved out a chance in the 63rd minute when he raced onto a through ball and cut back to create space, but he drove his shot straight at Dallas goalkeeper Jesse Gonzalez (three saves).
Ten minutes later, Dallas missed a tremendous chance when Cristian Colman seized upon a bad Portland giveaway in the penalty area but was denied by Attinella (one save) on a wide-open, 1-on-1 opportunity. Santiago Mosquera sent a follow-up effort from further out high and wide of the top far corner.
Then in the 81st minute, Timbers substitute Lucas Melano did well to reach Zarek Valentin's cross but redirected his volley straight at Gonzalez.