DENVER -- Jack Capuano made a surprising move to start Chad Johnson in goal Thursday night. It didn't change much for the Islanders, who had another ugly second period on their way to a 5-0 loss to the Avalanche, kicking off a grueling five-game road trip in the worst possible fashion.

The Islanders trailed 1-0 after one period despite controlling play and holding a 29-9 edge in shot attempts. The only breakdown came early, when the Isles' fourth line twice failed to clear the puck and Colorado's fourth line struck, with enforcer Cody McLeod banging in a shot 2:34 into the game.

Second periods have been bad even in games the Islanders have won -- they allowed three goals in the middle period of each of their last two games, which included a 7-5 win over the Stars. Thursday night, the Islanders began the second on a power play and got a few shots against goaltender Semyon Varlamov but could not push through.

They then got pushed around.

Nathan MacKinnon, last season's rookie of the year, scored his first of the season off a power-play scrum in front of Johnson at 3:25. All four Islanders penalty killers were splayed out in the crease, looking for a loose puck that squirted free to MacKinnon.

The Islanders got sloppier as the period wore on. The Avs' fourth line, which had produced zero goals in the team's first 10 games, struck again at 8:59, with Marc-Andre Cliche banking a no-angle shot off Johnson's pads and in.

Just 1:15 later, a harmless-looking dump-in became MacKinnon's second goal when no one picked him up racing down the slot to chip home Jarome Iginla's pass.

The Islanders continued to throw pucks on Varlamov, who stood strong and became the first goaltender to shut out the Islanders this season despite five Islander power plays. Varlamov finished with 40 saves.

The Avalanche did not put a shot on Johnson until the 13:40 mark of the third, but it went in. Erik Johnson blasted an unscreened shot past the goaltender for the final margin.

Jaroslav Halak was brought in this summer to be the Isles' No. 1 goaltender, but he's struggled and was shaky again in Tuesday's 4-3 loss to the Jets. Johnson, with similarly mediocre numbers to Halak outside of a 3-0-0 record, got the call despite Halak needing a bounce-back start.

"He's in the right place, he's fine -- he's our guy," Capuano said of Halak, who has a 3-3-0 record, 3.51 goals-against average and .889 save percentage. "We just want him to take a step back and relax. We know how good he can be."

But Halak has now had two rough outings and not gotten a chance to work out of his funk. He's certainly not alone among No. 1 goaltenders who have struggled to start the season -- Henrik Lundqvist sports a .907 even-strength save percentage, just ahead of Halak's .906 number -- but now, with three games in four nights after tomorrow night's game in San Jose, it's unlikely Halak will get a long run of starts.

There'll be no debate who starts in goal in San Jose. But the Islanders needed a tone-setting game to start this difficult road trip. This was certainly not the tone Capuano wanted his team to set.