The London Knights four-game winning streak came to a crashing halt in Plymouth Saturday.
The Whalers defeated the Knights 7-2 to move two points up on the Knights in the Western Conference standings.
It was a key game for both teams as the Whalers and Knights went into the contest tied for fifth in the Ontario Hockey League Western Conference.
Both teams had 69 points with the Whalers having a game in hand.
The Mustangs took a 2-0 first period lead on goals by Colin Martin and Stephen Sanza.
But the Whalers fought their way back with seven straight goals to take control of the game.
"It was 4-2 until midway through the third period," said Knights assistant coach Jacques Beaulieu. "It just looked like we ran out of gas. It was our third game in three nights with some travel and it just got to us.
"We competed but we just looked tired.
Stefan Noesen had two with singles to Mitchell Heard, Rickard Rackell, James Livingston, Alex Aleardi.
Igor Bobkov faced 30 shots in the London net.
The Knights were 0-for-7 on their power-play chances while the Whalers connected on 3-for-6.
"Special teams were a big difference," Beaulieu said. "We couldn't anything on the power play and they scored."
The game turned a little nasty late in the third period.
Whalers' Jamie Devane speared Knights Matt Rupert earning a double minor. Rupert then squared off with Heard.
The Knights' next game is Tuesday when they travel to Kitchener to play the Rangers.