Emmanuel Boateng scored his first MLS goal of the season in LA Galaxy's 3-2 defeat at FC Dallas on Saturday.
He climbed off the bench in the 77th minute to replace Chris Pontius and was on target on 83 minutes.
Maximiliano Urruti rifled a right-footer inside the near post past a diving David Bingham to give FC Dallas a 1-0 lead in the 28th minute.
Lamah doubled the advantage in the 44th, side-netting a feed from Diaz.
Ola Kamara scored in the 47th minute to trim the Galaxy’s deficit to 2-1, but Lamah headed home a high cross from Diaz in the 52nd before Boateng's capped the scoring in the 83rd minute.