The Red Bulls made it two wins from two games with a 1-0 victory at home over the Colorado Rapids on Saturday.
After rallying to beat Atlanta United last week, the Red Bulls earned another three points thanks to Eric Miller's own goal on the stroke of halftime.
The Rapids defender directed a cross into his own net as Red Bulls goalkeeper Luis Robles celebrated his MLS record 142nd consecutive start with a win.
There was a grandstand finish in Montreal as the Sounders scored a last-gasp goal in a 2-2 draw at the Impact.
The Impact were up 2-0 with seven minutes remaining until the Sounders stunned the home crowd in Montreal.
First, Nicolas Lodeiro converted an 83rd-minute penalty. Then substitute Will Bruin bundled the ball into the net in the fourth minute of stoppage time as the champions claimed their first point of the season.
Giovinco — the 2015 MLS MVP — hobbled off the ground in the 47th minute due to a leg contusion.
Quick-fire goals from Nemanja Nikolic and Arturo Alvarez helped the Chicago Fire past Real Salt Lake 2-0, Sporting Kansas City and FC Dallas played out a 0-0 draw, and the San Jose Earthquakes prevailed 3-2 against the Vancouver Whitecaps.