Defenceman Trevor Murphy was a team-worst minus-3 for the Spitfires (15-8-0), who had their four-game win streak halted.
Windsor's Alex Fotinos allowed four goals on 34 shots and was relieved by Dalen Kuchmey, who stopped the three shots he faced in the final 11 minutes of the game.
London went 1 for 1 on the power play while the Spitfires failed to score on three chances with the man advantage.
OTTERS 5 WOLVES 2
ERIE, Pa. — Dane Fox scored twice and set up one more as the Otters downed Sudbury.
Craig Duininck and Ray Huether responded for the Wolves (10-9-6), who lost for the first time in three outings.
Devin Williams made 37 saves for the Otters as Sudbury's Franky Palazzese turned aside 32-of-37 shots in defeat.
PETES 4 ICEDOGS 2
PETERBOROUGH, Ont. — Andrew D'Agostini stopped 31 shots as the Petes doubled up Niagara.
Steven Lorentz, Stephan Nosad and Josh MacDonald gave Peterborough (10-13-3) a 3-0 lead early in the second period and Nick Ritchie added another goal into an empty net late in the third.
Eric Ming and Mitchell Fitzmorris scored for the IceDogs (6-15-4), who are winless in seven games.
Christopher Festarini gave up three goals on 32 shots for Niagara.
STORM 6 WHALERS 2
PLYMOUTH, Mich. — Defenceman Zac Leslie scored four goals as Guelph toppled the Whalers.
Matt Mistele and Carter Sandlak supplied the scoring for for Plymouth (10-14-1).
Alex Nedeljkovic turned aside 47-of-52 shots for the Whalers.
SPIRIT 6 STING 2
SAGINAW, Mich. — Sean Callaghan scored twice and Jimmy Lodge had a goal and two assists as the Spirit defeated Sarnia.
Justin Kea and Dylan Sadowy had a goal and an assist each for Saginaw (14-8-3) while Daniel De Sousa added a single goal.
The Sting (8-16-1) got goals from Jimmy McDowell and Nikolay Goldobin.
Nikita Serebryakov made 23 saves for the Spirit while Taylor Dupuis stopped 40-of-46 shots for Sarnia.
BATTALION 2 COLTS 1 (SO)
BARRIE, Ont. — Blake Clarke scored the shootout winner as North Bay edged the Colts.
After two scoreless periods, Battalion (12-12-1) forward Barclay Goodrow made it 1-0 just over 11 minutes into the second.
Mitchell Theoret forced overtime when he scored for the Colts (13-8-3) at 17:05.
Danil Gibl made 38 saves for North Bay while Jake Smith stopped 22 shots for Barrie.
ATTACK 4 BULLS 3
OWEN SOUND, Ont. — Jaden Lindo scored once and set up two more as the Attack handed Belleville its fourth straight defeat.
Brandon Hope made 25 saves for the Attack. In his first OHL start, Braydon Banitsiotis stopped 26-of-30 shots for Belleville.