The Senators, owners of the NHL's worst power play, not only went 0-for-4 with the extra man, they also gave up a shorthanded goal to Brad Richardson in the second period and that proved to be the eventual winner in Colorado's 2-1 victory before a crowd of 17,728 at Scotiabank Place.
The loss was a record fourth straight on home ice to start the season for Ottawa (2-4-0-0) and marked the first time in more than four years that it's lost that many in a row in supposedly friendly confines.
"I don't know what we can do," Senators centre Mike Fisher said after Colorado (3-2-2) picked up its second win in as many nights. "The bottom line is everybody's got to play better. Guys aren't scoring, including myself, and it's just kind of snowballing."
Joe Sakic had the other goal for the Avalanche and Jose Theodore warmed up for Saturday and his first visit back to Montreal since being traded by the Canadiens last season by stopping 26 shots.
Colorado, which had knocked off the Toronto Maple Leafs 4-1 a night earlier, started slow but got better as the night wore on and won for the first time in Ottawa since Jan. 9, 1997.
The Avalanche had been 0-5-1 since then in its visits and 0-3-1 versus the Senators overall, last beating them on Dec. 3, 2001.
"I'm really happy with the way the guys played," Theodore said. "You saw that we bounced right back after that first period. We played really hard.
It's fun as goalie to see that your team is going to work hard in front of you."
Dany Heatley, who set a franchise record with 50 goals last season, scored his first of the season in the third period to make a game of it, but that was as close as Ottawa would come.
Martin Gerber, making his first start since Oct. 7, finished with 34 saves for the Senators, whose previous worst start was an 0-3-1-0 mark in 2001-02.
The last time Ottawa lost four in a row on home ice at any point in a season was March 21 to 28, 2002.
"We're just not on the same page on the ice," Ottawa defenceman Wade Redden said. "We just don't have the confidence or the poise on the ice. Until we do, teams are going to work us into the ice. That's what happened in the second period."
Off-season signing Joe Corvo, who suffered a fractured right foot while blocking a shot in a Sept. 22 exhibition game, made his debut on the blue-line and was supposed to help the Senators' power play.
However, the unit is now 1-for-34 on the year and has given up three shorthanded goals. Richardson's was the killer on Thursday.
"Power plays go through funks like that," Richardson said. "They've got good players and they're going to snap out of it but, luckily, it wasn't tonight against us."
On Wednesday, Theodore was on the bench in favour of Peter Budaj in Colorado's 4-1 win over Toronto.
He was back in net Thursday, trying to atone for a pair of losses in his previous two starts, including a poor performance in a 5-3 loss to Chicago on Monday night in which he gave up a couple of questionable goals.
He turned aside all 10 shots he faced through the opening period and, while Gerber faced the same number, the Avalanche were slowly began to turn up the heat.
"Jose held us in there and gave us a chance to get our legs under us," Richardson said.
Colorado outshot Ottawa 20-7 in the second and Sakic broke the deadlock just past the midway point of the period, taking a pass from Andrew Brunette and beating Gerber from close range for his third goal of the season.
The Senators' struggling power play put Ottawa into a bigger hole when it allowed Richardson to pick up an errant pass in his own end and break back the other way, beating Gerber over the shoulder with a shot from the faceoff circle.
"I just tried to put as much on it as I could and luckily it went in," Richardson said. "That was a big goal. Our penalty killing has been good all year."
Notes: Redden appeared in his 700th career game. It's the second most in Senators' history, trailing only Alfredsson's 712. . . . Defenceman Christoph Schubert and right-winger Brian McGrattan were healthy scratches for the Senators. . . Ottawa is back in action on Saturday when New Jersey visits. . . With Jordan Leopold (hernia), Brad May (shoulder), Cody McCormick (chest), George Parros (shoulder) and Pierre Turgeon (shoulder) all out injured, defenceman Kurt Sauer was the only member of the Avalanche to be scratched from the lineup. . . . Defenceman Karlis Skrastins' NHL-best consecutive games streak reached 440 straight contests.