Tatar gave New Jersey a 1-0 lead at 6:29 of the first period, scoring from the slot off a pass from Fabian Zetterlund from behind the net.
Dylan Guenther tied it 1-1 at 9:04 when his attempt from the left post deflected in off Devils defenseman Jonas Siegenthaler with five seconds remaining on a power play.
Jack Hughes scored 23 seconds later on a snap shot from the right face-off circle off a give-and-go with Tatar to put the Devils back in front 2-1.
"[Tatar's] been important for us," Siegenthaler said. "He's a veteran guy, knows how to score, and when he talks in the locker room, everybody listens because he has a lot of games under his belt."
Hughes, who has been attempting to round out his defensive game this season, has 12 points (four goals, eight assists) in his past nine games.
"I've said this before, he's got to get comfortable being a little bit uncomfortable with the way we need to play at certain times," Ruff said. "I thought later on in the game, like the second and third period, I thought he was really skating, creating opportunities, getting back above the puck.
"His defensive awareness was [really] good, and that's the part we've been talking about as a team. To be able to win these games, I use the line, 'Don't get scored against.' So do what you can to not get scored against."
Keller tied it 2-2 with a power-play goal at 8:19 of the second, skating down the slot before finishing with a forehand-to-backhand move.
"We had a similar play in the first and it kind of went under my stick, so we kind of watched it and it worked out perfectly, and [Travis] Boyd made a great play under the guy's stick," Keller said. "When I saw the hole, I tried to get in there as fast as I could."