Alex Roldan converted the decisive spot-kick for the Seattle Sounders as they came out 5-4 victors in a penalty shootout with the 10-man Houston Dynamo in the MLS Cup playoffs.

Roldan stepped up to slot home the winning penalty after a 0-0 draw on Monday, putting the Sounders a game up in the best-of-three series.

Adalberto Carrasquilla saw red for his part in a fracas midway through the second half at Lumen Field, where Erik Sviatchenko's miss in the shootout proved costly.

The Sounders were ultimately worthy winners, though, given they had 19 shots to Houston's seven, with the visitors failing to get a single attempt on target and mustering just 0.45 expected goals (xG) before penalties were required.

And Seattle held their nerve in the shootout, converting all five of their penalties.

In Monday's other playoff game, Yamil Asad grabbed FC Cincinnati's winner in a 1-0 victory over New York City FC.

Luciano Acosta, the 2023 MLS MVP, delivered a brilliant cross from which Asad headed home in the 51st minute.

Teenage Hadebe, Luca Orellano and Nicholas Gioacchini squandered chances to put Cincinnati 2-0 up, but NYCFC could not make their luck count, and their frustration was compounded when Tayvon Gray was dismissed for a flailing arm into Acosta's face.

Acosta was excellent throughout, creating seven chances in total and having four shots.

He has now recorded 14 goal contributions in his career against NYCFC (six goals, eight assists).

"I knew [Acosta] was going to play the ball to me," Asad said. "It's too easy to play with him. He's our MVP, he played a great game."