When Hartley was dismissed, Colorado was in fourth place in the Northwest Division with 33 points and was one of five Western Conference teams that had surrendered more than 80 goals.
De Vries sparked the Avalanche's three-goal second period and fellow defenseman Rob Blake converted a drop pass from Jeff Shantz into his first shorthanded goal of the season. It came 35 seconds after teammate Derek Morris was penalized for holding.
Six minutes later, Jim Dowd's power-play goal got Minnesota within 3-2. But Dean McAmmond restored Colorado's two-goal cushion with 19 seconds remaining in the period.
The Avalanche, however, had to hang on for their fifth home win as Patrick Roy made 16 of his 45 saves in the third period.