On Sunday at the Avalanche’s optional practice, the rink rats — including the most notorious of all, Ryan O’Reilly — helped set up an innovative version of a “shooter tutor” contraption in one of the nets and continued to fire away.

The shooter tutor won’t be in the Avalanche net on the road against the Arizona Coyotes on Tuesday. Barring a sudden Semyon Varlamov recovery from a groin injury, Patrick Roy will choose between Reto Berra and recent call-up Calvin Pickard, 22.

The Avalanche has a lot on the line with Berra.

His often-shaky play has done little to quiet the fears that Colorado made mistakes both when it acquired him at the trading deadline on March 5 from Calgary, and — perhaps even more important — signed him to a three-year, $4.35-million contract extension only nine days later.

That’s less than a fourth of what Varlamov makes, but the 27-year-old Swiss is under contract through the 2016-17 season. Yet it’s still a significant commitment.

It isn’t just a money issue, but also a competitive one in a league with a hard salary cap, guaranteed contracts, and limited potential buyout relief. A long-term commitment to a presumed backup still should come with a belief that he not only can capably play 25 games a year, but take over the No. 1 job for stretches in case of injury or even because he deserves to stay in the net .

Berra has had solid games this season, and at least didn’t reprise his shaky showings in his cameo appearances down the stretch last season. But with Varlamov out, this is his latest chance to win over the skeptics, and so far, he’s failing. After Roy pulled him when Carolina took a 3-1 lead late in the first period Saturday night, Pickard shut out the Hurricanes the rest of the way in a 4-3 Colorado victory.

Berra’s save percentage is below the Astrom Line, at .895, his goals-against average is 3.16.

Also at stake here is Avalanche organizational goaltender evaluation credibility. And that’s a very strange thing to have to say about a team that has Roy as its head coach and Francois Allaire, renowned if occasionally a bit controversial as a goaltending whisperer, as its goaltending coach.

I was on the Avalanche trip at the trading deadline in March when Colorado acquired Berra, and to this day I remain a bit mystified by the organization’s seemingly sudden dissatisfaction with Jean-Sebastien Giguere. He was in the twilight of his career, his contract was up, he was having back issues, but he had been terrific at the start of the season. Unless the Avalanche got a steal at the deadline to acquire a guy perfect for the backup role (or more) in future seasons, the trade — and the sudden contract extension — made little sense. Colorado could have dealt with the backup issue in the offseson.

It might be too soon to write off Berra, who didn’t come over from Switzerland to play in the NHL until a year ago, when he was 26. Still, his Saturday yanking, which happens to the best of NHL goalies, seems to be part of a pattern of shakiness. Joe Sakic was quite open that Allaire, who spends considerable time tutoring goalies in Switzerland at camps and privately, recommended Berra, who struggled as a rookie with the Flames last season before the trade. The thought apparently was that he was going through a difficult transition to the North American game with a bad team, and that he would get better. Much better.

He hasn’t yet lived up to that faith.

There will come a point where Sakic, Roy and everyone else involved will have to confront and deal with a possible misstep.

Perhaps it’s ludicrous to think that the fiercely competitive Roy ever is going to let denial and saving face be a factor in deciding how — or even if — to use Berra, and whether he’s deserving of being locked in as Varlamov’s backup.

But admitting mistakes can be difficult.

Terry Frei: tfrei@denverpost.com or twitter.com/TFrei