Denis Bouanga scored his first MLS goal in the fifth-minute of second-half stoppage time to lift visiting LAFC to a Supporters Shield-clinching 2-1 victory over the Portland Timbers on Sunday afternoon.
Carlos Vela added his 12th goal of the season earlier in the second half as LAFC (21-8-4, 67 points) captured the trophy awarded to the best regular-season finisher in MLS for the second time in five all-time seasons.
LAFC have a game remaining and a three-point lead on second-place Philadelphia, but can't be caught because they hold the first tiebreaker of more total victories.
Dairon Asprilla scored his ninth goal of the season to level the game in the 81st minute for Portland (11-9-13, 46 points), which lost for the first time in six matches. The Timbers could have clinched a playoff spot with a victory.
The Timbers are sixth in the Western Conference and two points above the playoff line, but will fall behind eight-place Real Salt Lake if they lose in Salt Lake City in the regular-season finale for both teams next Sunday.
It appeared LAFC lost its best chance at securing all three points when a potential penalty kick foul on Portland's Claudio Bravo resulted in a lengthy video review, but no infraction.
But Bouanga had one more chance for the visitors. After reaching a ball down the left, he cut inside between Yimmi Chara and Dario Zuparic, then struck a low shot that deflected of the lunge of defender Bill Tuiloma and past goalkeeper Aljaz Ivacic.
Vela's brilliance had given LAFC the lead in the 51st minute. Portland looked to be defending LAFC comfortably, but had dropped pretty deep with most of their team inside their own penalty area.
Kellyn Acosta played a ball across the top of the box to his right, where Vela received it, cut slightly inside and curled a left-footed shot beyond the dive of Ivacic and into the top corner.
The Timbers mounted considerable pressure in search of an equalizer, and Bravo's header struck the crossbar in the 71st minute. Bravo was involved in the equalizer 10 minutes later, sending in a well-weighted, outswinging cross from the left.
Asprilla rose and beat Eddie Segura to the ball, sending a powerful header past Maxime Crepeau from about 6 yards away.