Patrick Kane scored his 36th goal and added two assists to extend his point streak to 18 games - with 14 goals and 26 assists during the stretch- the longest by a player in the NHL this season. Dylan Strome also had a goal and two assists in his fourth three-point game since joining the Blackhawks on Nov. 25, and Brandon Saad, Gustav Forsling and Jonathan Toews also scored.
The 21-year-old DeBrincat's five points set a career high. His fourth NHL hat trick gives him 32 goals in his second season.
Colin White had two goals and an assist, Thomas Chabot scored twice, and Mark Stone, Bobby Ryan and Rudolfs Balcers also had goals for NHL-worst Ottawa, which lost for the eighth time in its last 11.
The Blackhawks led 5-4 after a wild first period loaded with defensive breakdowns and few soft goals. Both starting goalies - Chicago's Collin Delia and Ottawa's Anders Nilsson - were pulled before the end of the period.
Cam Ward got the win as he finished with 24 saves on 28 shots.
White's second goal, on a wrister from the left circle, tied the score 1:32 into the second.
DeBrincat completed his hat trick on a screened one-timer at 8:19 to put Chicago back ahead. Forsling ripped in a screened slap shot from inside the blue line 1:12 later to increase the Blackhawks' lead to 7-5.
Set up by DeBrincat, Toews whipped in a power-play goal at 3:51 of the third to give Chicago a three-goal lead.
Chabot scored from the left wing at 9:01 to make it 8-6, then buried a rebound with 5:17 left to pull Ottawa within a goal.
Chicago killed an Ottawa power play over the last 1:40 with the Senators' Craig Anderson pulled for an extra attacker.
Ottawa jumped out to a 2-0 lead 2:40 into the game on a power-play goal by Ryan and even-strength score by Balcers 34 seconds apart.
DeBrincat tied it at 2-all just 2 1/2 minutes later when he was left wide open for power-play and even-strength goals in a 1:13 span.
White's first goal put the Senators back ahead 3-2 at 7:55 and chased Delia, who faced 10 shots.
Kane and Strome connected 46 seconds apart to put Chicago ahead 4-3 with 6:38 left Strome leisurely poked a loose puck past Nilsson on the short side, prompting Ottawa coach Guy Boucher to send in Anderson. Nilsson gave up the four goals on 12 shots.
Anderson, who had missed the previous three games with an eye injury, allowed four goal on 30 shots.
Saad was wide open at the edge of the crease for a tap-in with 5:07 left in the first to made it 5-3, then Stone scored countered from the slot with 2:14 left to pull Ottawa within one.
NOTES: Kane has assists in 17 straight games, matching Wayne Gretzky and Paul Coffey for the third longest assist streak in league history. Only Gretzky (23 games in 1990-91) and Adam Oates (18 games in 1992-93.) have had longer such streaks. ... The nine goals by both teams in the first period set a Senators team record for combined goal in a period. ... Chicago D Brent Seabrook sat out with an abdominal strain. ... Senators F Mikkel Boedker returned after missing seven games with an abdominal injury. .Chicago made a minor-league deal before the game, acquiring F Peter Holland from the New York Rangers for D Darren Raddysh. ... The Senators are rumored to be shopping pending unrestricted free agents F Matt Duchene, D Stone and F Ryan Dzingel as next Monday's trade deadline approaches. Scouts from no fewer than nine other NHL teams were in the press box, including two from Winnipeg.
Senators: At New Jersey on Thursday night.
Blackhawks: At Detroit on Wednesday night.
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