Former track star Ema Boateng scores two goals to help Galaxy advance in MLS playoffs

Galaxy Coach Bruce Arena’s busy off-season netted him two World Cup veterans and a former MLS player of the year, a collection he augmented last month by luring Landon Donovan out of retirement to join a team anchored by Robbie Keane, Steven Gerrard and Giovani dos Santos.

The result was arguably the deepest and most star-studded roster in league history.

But on Wednesday night the team’s season turned on the performance of an unheralded former track star from Ghana, Ema Boateng scoring two first-half goals to lift the Galaxy to a 3-1 victory over Real Salt Lake in an elimination-round playoff game at the StubHub Center.

Alan Gordon also had a first-half goal for the Galaxy, who move on to face the Colorado Rapids in the Western Conference semifinals.

The two-leg playoff begins Sunday at the StubHub Center and concludes Nov. 6 in suburban Denver, where the winner will be determined on aggregate goals.

And it seems fitting that a Galaxy team rife with big names and bigger personalities was led there by the smallest and quietest player in their locker room.

“Teams in every sport have a different collection of players that make your team effective,” Arena said, referring to Boateng’s usual supporting role. “You can’t have 11 Robbie Keanes on the field, you have to have the right balance.

“Today he wasn’t a complementary player. He took the game into his own hands.”

Or his feet, because Boateng, 22, is also the fastest player on the team and his speed helped set up both of his goals.

The first, in the 26th minute, came on a stirring individual effort in which he dribbled into the center of the box, bounced off a defender and maneuvered through at least three others before beating goalkeeper Nick Rimando with a low right-footed shot toward the far post to give the Galaxy a 2-1 lead.

Boateng, who was born in Ghana but attended high school in Carpinteria, later took a pass from Gordon on the right flank, eluded defender Demar Phillips as he curled toward the goal, then pushed a left-footed shot past Rimando just inside the post.

The two scores gave Boateng four for the season, all against Real Salt Lake, which was no doubt happy to see him leave to a standing ovation from the announced crowd of 18,124 in the 76th minute.

“I’ve had some good games but I think this one is really up there,” Boateng said. “It’s an important win for the team. Guys are trusting me a little bit more and they’re giving me the confidence to kind of take defenses on.”

Gordon, who had the assists on both of Boateng’s goals, got the scoring started in the 14th minute with the second playoff goal of his career and first since 2012.

Real Salt Lake’s only score — a murmur of mild protest really — came on Joao Plata’s penalty kick in the 21st minute.

The goal was only the third in six weeks for Real Salt Lake, which ended its season by going winless in its final eight games.

“These last six, seven games the goal got really small for us,” RSL Coach Jeff Cassar said. “Just disappointed. Not just in this game but in the last seven.”

kevin.baxter@latimes.com

Twitter: kbaxter11