Cale Makar had three assists and Valeri Nichushkin scored twice for the Avalanche (10-5-0), who have won two straight. Devon Toews and Samuel Girard each had a goal and an assist, and Alexandar Georgiev made 15 saves.
Kiviranta was in Avalanche training camp on a professional tryout, started the season with Colorado of the American Hockey League then made his Avalanche debut in Monday’s 5-1 win at the Seattle Kraken.
Sam Carrick and Max Jones scored, and Lukas Dostal made 30 saves for the Ducks (9-7-0), who had won five straight road games after defeating the Nashville Predators 3-2 on Tuesday.
Girard scored to make it 1-0 Avalanche when he banked in a loose puck off a sprawling Alex Killorn during a goalmouth scramble at 6:40 of the first period.
Nichushkin extended the lead to 2-0 after deflecting Toews’ point shot into the left corner of the net at 12:41.
Carrick cut the lead to 2-1 when he redirected Radko Gudas’ one-timer from the blue line at 19:27.
Fredrik Olofsson made it 3-1 Colorado when he scored on a one-timer from just above the circles that caromed off Dostal’s glove at 14:33 of the second period.
Ross Colton scored to make it 4-1 when he chased down a pass from Logan O’Connor and finished with a breakaway at 3:53 of the third period.
Nichushkin scored on the power play to make it 5-1 when he deflected Makar’s point shot at 5:51 of the period.
Jones made it 5-2 after Adam Henrique fought off Bowen Byram and passed behind his back and across the crease to Jones for the tap-in at 9:41.
Kiviranta scored his first goal with the Avalanche to make it 6-2 when he split two defenders and beat Dostal short side with a wrist shot at 13:13 of the period. He then set up Andrew Cogliano on a 2-on-1 to make it 7-2 just 31 seconds later.
Toews finished a cross-zone pass from Makar into the open net at 15:18 for the 8-2 final.
