FC Dallas rode an early goal to a 1-0 win against MLS Cup holders Toronto FC on Friday night at BMO Field.
Oscar Pareja's team took the early lead when Max Urruti redirected a Kellyn Acosta shot past Clint Irwin in the 11th minute to make it 1-0.
Toronto should have been level minutes later, but Jesse Gonzalez kept out Sebastian Giovinco's spot kick after Matt Hedges fouled the Italian in the penalty area.
Urruti missed a golden chance to make it 2-0, heading wide of the far post in front of an open goal when Michael Barrios had set him up with a neat chip back across the six-yard box.
The hosts couldn't find a way through in the second half, with Gonzalez making several fine saves, including a stoppage time scoop in front of a wide-open goal when Toronto should have scored.
The loss sees Greg Vanney's banged-up team fall further adrift of the Eastern Conference leaders in a stuttering start to the 2018 campaign.