The 18-year-old rookie scored three goals to lift the Vancouver Whitecaps to a 4-1 victory over the Seattle Sounders on Wednesday, keeping his team's slim playoff hopes alive.
He also became the youngest player in MLS history to score three goals in a game.
"I'm more nervous in this interview than I was in the game," Manneh said. "This is the type of games that every player wants to play in. This is the kind of game we dream to play in. To play in front of this crowd is amazing. All we can do is get excited and play the game."
Manneh was especially efficient for Vancouver (12-11-9), scoring on all three of the shots that he put on frame. He had come into the game with just three previous starts and 529 minutes in which he had managed to score two goals and register three assists.
"Phenomenal game and a great night for Whitecaps fans to remember for a long time," Whitecaps manager Martin Rennie said.
"We played a great game tonight. We played some great stuff, kept good possession of the ball, moved the ball well in a tough environment to come to against our biggest rival. I'm really proud of the players. We worked extremely hard and took our chances when they came."
All three of Manneh's goals came after he was able to slip behind the defence.
The first was in the 12th minute, when Daigo Kobayashi intercepted Jhon Kennedy Hurtado's clearance attempt and volleyed it to Manneh. With just one defender to beat, Manneh got behind the defence and poked it past Sounders goalkeeper Michael Gspurning.
Manneh added another in the 42nd minute, catching the Sounders defence on a counter-strike. Young-Pyo Lee started it with a pass along the sideline to Camilo Sanvezzo, who back-heeled it to Manneh. Again with just a single defender to beat, Manneh pushed ahead and beat Gspurning with a low shot.
The capper came in the 53rd minute after Manneh worked a give-and-go with Kobayashi at the top of the penalty area. Manneh got free on goal and put his shot between Gspurning's legs for the first hat trick in the Whitecaps' MLS history.
"We joked before that you're never exactly sure what you're going to get with an 18-year-old," Rennie said. "But he's unbelievably talented. ... With younger players, you're not always going to get that consistent level of performance but we did talk about it before that if he showed up he could make a huge impact on the game and he did."
Nigel Reo-Coker added his first goal of the season in the 82nd minute to cap the scoring on a poor effort by Gspurning.
Seattle's lone goal came in the 69th minute from Mauro Rosales.
The win moved the Whitecaps to within three points of the final playoff spot in the Western Conference.
They will have to win their final two games against the Colorado Rapids — away and at home — in order to have any chance of qualifying for a second straight year. They'll also need the San Jose Earthquakes drop at least two points in their final two matches.
Seattle (15-10-6) meanwhile is still one point back of Real Salt Lake for the top spot in the Western Conference.
The Whitecaps at least have some serious momentum.
"We needed that tonight," Rennie said. "These players, I don't think people really believe in them as much as they should. I think the most important thing is the players are really believing in themselves. ...
"Tonight was a really good night for us and we'll enjoy that. Then we have to get focused on the next one."