Ryan Getzlaf played his 1,000th NHL game, all with the Ducks, and had an assist on Gudbranson's goal to stretch his point streak to five games (four goals, two assists).
"It has probably been a great privilege for everyone around here watching that young man grow up," Anaheim coach Dallas Eakins said of Getzlaf. "To play 1,000 games in one jersey is a very hard thing to do and we are all very, very proud of his accomplishment."
The Blackhawks won the opening face-off in overtime, and Toews brought the puck down the right side before sliding a pass to Kane for a one-timer.
"They have a habit of that," Chicago coach Jeremy Colliton said of Toews and Kane. "That's why you put them out there together, because they find a way. It was a big goal for the team."
Anaheim entered the game 30th in the NHL in power-play efficiency (8.3 percent) and was 0-for-3 before Ritchie scored with the man-advantage to tie it 2-2 at 6:17 of the third period.
Boqvist, the No. 8 pick of the 2018 NHL Draft who made his NHL debut Saturday, gave the Blackhawks a 1-0 lead at 9:21 of the first period when he banked a shot off the inside of the right post three seconds after Chicago's first power play ended.
"He's got such a good shot that, more likely than not, it was going in the net," Kane said. "He had a chance [Saturday] night in overtime. It would have been fun to see him score that one, but his first goal in his first two games in the League, he's got a lot of upside, lot of potential, so good start for him."
The Ducks were called for two penalties 50 seconds apart later in the first, and Alex DeBrincat scored on a 5-on-3 advantage at 15:33 to make it 2-0 after a cross-ice feed from Kane.
Lehner, who got his 100th NHL win, then made a save on Derek Grant's breakaway at 16:30 to keep it a 2-0 game.
"We did a good job scrambling together when it was scramble mode," Lehner said. "[The defense] played real hard and helped me out, and we stuck in there together."
Gudbranson, who was traded to Anaheim from the Pittsburgh Penguins on Oct. 25, took a shot from the point that caromed through traffic and past Lehner at 12:39 of the second period to make it 2-1.
"[The Blackhawks] playing [Saturday] night was an opportunity for us to really jump on them hard," Eakins said. "I'm not sure we quite accomplished what we wanted there, but always good to come back and get back in the game."