With all the criticism being directed at Jason Zucker the past week from coach Mike Yeo, it started to look as if the speedy winger's spot on the Wild's opening-night roster was on thin ice.

Sunday, Zucker fell through, assigned to the Iowa Wild after being outperformed by Nino Niederreiter in training camp for the second-line left wing position.

"We're not prepared to put [Zucker] on the fourth line right now, and we're not prepared to have him be a healthy scratch," Yeo said. "What you saw on the ice [in Sunday's practice] was us gearing up for Game 1, and we're really not focused on anything beyond that."

Barring injuries this week or transactions, Mikael Granlund, Niederreiter, former UMD Bulldog national champion Justin Fontaine and 19-year-old defenseman Matt Dumba all will be on the Wild's opening night roster. Fontaine and Dumba are expected to make their NHL debuts Thursday against the Los Angeles Kings.

Jake Dowell, despite the fact he has to be paid his $700,000 NHL salary in the minors, also was assigned to Iowa on Monday. That leaves 22 on the roster — one fewer than the maximum. That would allow the Wild to add a player off the waiver wire or via trade, eventually sign free agent David Steckel or simply keep it open and save salary-cap space.

Niederreiter will start the season next to Charlie Coyle, who grabbed the open No. 2 center job early in camp, and veteran Dany Heatley. Granlund will start the season playing right wing on the third line with veterans Matt Cooke and Kyle Brodziak.

Jason Zucker will be feeling down for a while after being sent to Iowa on Sunday. He later tweeted: “Nobody to blame but myself. Have to be better and will be better!’’

Granlund also will be the puck distributor on the No. 2 power-play unit with Coyle and Niederreiter, can slot up to the second line if needed and gives the Wild the versatility of having a player who can move to center.

Yeo said Niederreiter "earned it" and gives the Wild a big body who can shoot, skate and handle the puck on a scoring line.

"He played like a top-six forward in training camp," Yeo said. "Granny had a good camp, too. We spent the entire camp really looking at him as a centerman. We feel we can get a lot out of him as a winger, too. He showed that he's battled harder, he's shown that he's faster, defensively he did a very good job for us, and we feel he can be a good complement to the [Cooke-Brodziak] line."

Fontaine, a smart, hard-working player with sneaky skill who had nothing else to prove in the minors and can slot up and down the Wild's lineup, had a strong camp and would have required waivers to get to Iowa. Yeo essentially said that at 25, the Wild doesn't have to stress putting him in a fourth-line role with Zenon Konopka and Torrey Mitchell.

Yeo said Zucker was obviously disappointed, and the message was to make sure he was on top of his game for an eventual callup.

"We know that he's there and to be perfectly honest, I like the idea that everybody on our team knows that he's there," Yeo said. "It shouldn't be too difficult to make sure that you're ready to go knowing that there's a guy like that waiting in the wings."

Zucker declined to comment as he left Xcel Energy Center with his hockey bag and sticks, but he later tweeted: "Nobody to blame but myself. Have to be better and will be better! See you soon Minnesota!"

It'll be interesting to watch how Dumba is eased into the Wild lineup. Veteran Clayton Stoner looks to be the odd guy out whenever Dumba plays, so there may be times Yeo decides to give Dumba the night off and play Stoner.

It's a big transition from junior hockey, but the big-shot Dumba looks like he will be paired with veteran Keith Ballard at even strength Thursday and man one of the second power-play unit's points with Jared Spurgeon.

Dumba knows the Wild still can return him to Red Deer before he plays in 10 games without burning the first year of his contract, so he said: "I'm not taking anything for granted. I know that just because I'm in this locker room now, I can be back in junior in the next month. I'm going to do whatever it takes to stay here full-time."

After Sunday's practice, the Wild bused to Duluth, where it will practice Monday and Tuesday. The Wild had a team-building exercise Sunday, will golf Monday and have two team dinners.

Fontaine is excited to return to his college rink as an NHLer.

"It'll be a good feeling," Fontaine said. "This is something I've been working toward for a lot of years."

Etc.

• Goalies Niklas Backstrom (sore) and Josh Harding, who left Friday's preseason game not feeling well, both practiced Sunday. Mitchell, tripped hard late in Friday's game, skated well in Sunday's practice. …

• Tuesday's 10 a.m. practice at AMSOIL Arena is free and open to the public.

• Injured Brett Bulmer was also assigned to Iowa.