"The guys did a great job in front of me, getting in the shooting lanes and keeping the puck off me," said Andersen, who had back-to-back shutouts for the first time in his NHL career. "This was a big game because Detroit is trying to catch us and we got some separation."
WATCH: All Maple Leafs vs. Red Wings highlights
Andersen had an assist on Nikita Soshnikov's third-period goal, the second time in his NHL career he's had a shutout and an assist.
"I saw [Soshnikov] was wide open on the wing so I tried to bank it off the wall and hit him," he said. "It doesn't always work, but it did that time."
The Red Wings (20-20-9), who had a six-game point streak end, lost their fourth straight (0-1-3) and fell six points behind the Maple Leafs in the Atlantic Division. Toronto has three games in hand.
"I'm not worried about them right now," Red Wings coach Jeff Blashill said. "I know we've got to be a little better. This was a huge game and we lost it. Now we have to come back after the [All-Star] break and keep grinding."