CHICAGO -- Alex Ovechkin was kicked out early, the Washington Capitals fell behind 3-0 and that's when they showed why they have the NHL's best record and highest-scoring offence.
Nicklas Backstrom scored unassisted with 1:50 left in overtime -- his second goal of the game -- to give the Capitals a 4-3 comeback victory Sunday.
"It's a strong sign, especially now at the end of the season," Backstrom said. "We know he (Ovechkin) is a key to our team and he scores a lot of goals. We have shown that we can play, that our other key players can, play, too."
After his sprint up the side, Backstrom manoeuvred around Chicago defenceman Brent Seabrook in the left circle and beat Antti Niemi.
Ovechkin, the two-time MVP and the league's leading scorer this season, got a game misconduct in the first period for knocking Chicago's Brian Campbell into the boards.
"There's nothing I can do right now. He just fell and this happens," Ovechkin said.
Jonathan Toews had two goals and John Madden scored once for the Blackhawks, who had their second crushing defeat in as many days.
They lost 3-2 in Philadelphia on Saturday, giving up two goals in the final two minutes, including the game winner with two seconds to go.
Down 3-0 in the third Sunday without their top player and with Niemi playing well, the Capitals dominated play.
Brooks Laich scored on a power play at 5:29 to make it 3-1. A couple of seconds after the Caps' 5-on-3 power play had elapsed, Backstrom converted a rebound at 7:32. Thirteen seconds later, Eric Fehr scored from just outside the crease, tying the game, silencing the crowd at the United Center and forcing Chicago to take a timeout.
The Capitals had an 11-1 shots-on-goal advantage in the third period.
Ovechkin raced up the ice and from behind drove Campbell into the boards with 7:44 left in the first period.
Campbell stayed down for several minutes before he was able to leave the ice with a trainer at his side and then headed to the locker room. He did not return to the game. He has an upper-body injury and will not make the Blackhawks upcoming road trip to the West Coast.
Ovechkin went to the penalty box after being assessed a five-minute boarding penalty and then into the locker room after being given a game misconduct.
"I don't think it was a real good check. He just kind of fell and it was a dangerous moment. It was not a hard hit. I just wanted to push him," Ovechkin, the two-time MVP, added.
"I didn't hit him hard. I pushed him, but he fell bad. It probably looks bad. I thought it was going to be two minutes, but the linesman came to me and said 'Game over."'
Ovechkin was given two game misconducts earlier this season, the first for a shoulder check and the second one for a kneeing incident that eventually led to a two-game suspension.
"The league will do what they do," Chicago coach Joel Quenneville. "Soupy (Campbell) is going to be out for a bit here. It was a dangerous hit."
Blackhawks defenceman Niklas Hjalmarsson would like to see Ovechkin penalized.
"I hope they take a good look and suspend him for a couple of games," he said.
The Blackhawks were able to capitalize on the penalty after Ovechkin's hit. They had a 5-on-3 power play after a second penalty on Alexander Semin, who crashed into Niemi at the end of a breakaway.
Toews scored for the second time in the first period, poking in a rebound from in front after a shot from Patrick Sharp. That made it 2-0.
Madden scored on a redirect on a long pass from Duncan Keith to make it 3-0 in the second.
"We've got the most skill in the league, on any team," Toews said. "There's no reason, up 3-0, we can't go out and finish the team off."
With the teams playing 4-on-4, Toews took a nice crossing pass from Hjalmarsson for the first score seven minutes into the game.
Niemi, in a battle with Cristobal Huet to determine the team's No. 1 goalie before the playoffs, made 26 saves. Jose Theodore had 20.
Notes: Blackhawks RW Marian Hossa, who scored his 20th goal and had his 20th assist in Saturday's loss at Philadelphia, was scratched with an upper-body injury. .. The Capitals reached 100 points in their 69th game. Backstrom also had an assist, giving him at least 55 in each of his first three seasons.