MacKinnon has 31 points (12 goals, 20 assists) during his run, which is the longest active point streak in the NHL and matched Toronto Maple Leafs forward William Nylander for the longest this season. MacKinnon also extended his season-opening home point streak to 17 games (15 goals, 22 assists).
Mikko Rantanen scored twice, and Valeri Nichushkin had three assists for the Avalanche (20-11-2), who went 4-for-5 on the power play and won for the fourth time in six games. Alexandar Georgiev made 41 saves.
Drake Batherson had a goal and an assist for the Senators (11-17-0), who have lost six in a row, including their first two with Jacques Martin as coach. Joonas Korpisalo made 33 saves.
Ottawa was 1-for-6 with the man-advantage.
MacKinnon gave Colorado a 1-0 lead on a power play at 2:43 of the first period, one-timing a feed from Jonathan Drouin.
Josh Norris tied it 1-1 at 15:13 when he one-timed Batherson’s backhand pass past a sprawling Georgiev.
Ridly Greig gave the Senators a 2-1 lead just 15 seconds later at 15:28. Dominik Kubalik tipped a shot from the point, and the puck rolled up and over Avalanche defenseman Devon Toews and off Georgiev before landing on Greig’s stick for the tap-in.
MacKinnon tied it 2-2 with a snap shot from between the circles that went under the left leg of Korpisalo at 18:28. It was MacKinnon’s 300th NHL goal.
Jacob Bernard-Docker put Ottawa back in front 3-2 at 1:32 of the second period with a slap shot from the blue line that went off Colorado defenseman Cale Makar and got between Georgiev’s pads.
Batherson extended the lead to 4-2 at 14:47 when he corralled a cross-zone pass from Vladimir Tarasenko and fired it in far-side from the left face-off circle.
Rantanen cut it to 4-3 on a power play at 19:43 with a shot from the right circle.
MacKinnon completed the hat trick at 6:16 of the third period with a wrist shot from the left circle while on the power play to tie it 4-4. The Senators challenged for offside, but the goal was upheld following video review.
Rantanen then gave the Avalanche a 5-4 lead on a deflection of MacKinnon’s pass at 7:10 for their fourth power-play goal.
MacKinnon scored into the empty net at 19:37 for the 6-4 final.
