Calgary's problem is simpler and worse. The Flames have scored 1 goal in 3 of their 5 games and have given up 6 twice, both times to Seattle. They're also short up front: Jonathan Huberdeau went on injured reserve with a hip injury before the season, and Samuel Honzek is out. Their best stretch of hockey this year was the 2nd period on Saturday, when they climbed out of a hole against the Ducks. The 3rd period showed how hard it's been for them to keep that going.
Anaheim's start has been built on the road. They won at Vegas, at Winnipeg and at Calgary, and they're 1-1 at Honda Center after beating Florida and losing 5-2 to Edmonton. The 5-1 win in Winnipeg was the most complete game they've played. Tuesday also gives them something they didn't have Saturday: they'll have had a couple of days off, and they won't be on tired legs.
The Gauthier update is the thing to watch before Tuesday. Without him, the Ducks' forward group is thin enough that Calgary should get more room to create than Saturday's result suggests. With him, Anaheim has more skill available than a Flames team allowing over 5 goals a game has shown it can handle. Calgary needs a goalie to steal one or a power play to finally score. It hasn't had either yet.