Not much rattles, or rattles by, Ducks backup goalie Viktor Fasth

Before he became an overnight sensation, Viktor Fasth wasn’t certain he would get anything more than workload scraps when the Ducks were playing back-to-back games.

Coach Bruce Boudreau made that clear during the abbreviated training camp, given the urgency of a 48-game season and the familiarity he had with iron-man goaltender Jonas Hiller. Hiller made 73 starts in 2011-12, including 32 in a row in one stretch.

But after Fasth, 30, defeated Ducks’ nemesis Nashville in his league debut in a stirring shootout performance, Boudreau backed off his preseason plan and let Fasth make starts against Minnesota (victory, one goal allowed), then-unbeaten San Jose (victory, one goal allowed) and at Colorado (shutout victory).

“He was winning and not allowing goals,” Boudreau said when asked what he saw in Fasth that so impressed him. “When you do that, you’re going to play. There’s just an incredible calm about him. Nothing rattles him.”

Hiller suffered a lower body injury Feb. 8 at Dallas, and Fasth won four more starts on the road to forever alter the goalie rotation and help the Ducks (13-3-1), who enter Wednesday night’s home game against Nashville tied for the second-most points in the NHL.

“He’s come in and worked his rear end off and the guys notice that,” Ducks General Manager Bob Murray said. “That’s a huge thing. Who wants to get hit with all those pucks in practice?

“We now have two really good goaltenders, and before all is said and done this season, we’ll need both of them. It’s a very good situation to be in.”

Fasth lost his first game in nine starts Monday night at the defending Stanley Cup champion Kings, but the Ducks already had been so taken with the 6-foot, 186-pound goalie that last week they handed him a two-year extension worth $5.8 million through 2013-14. (Fasth fell one short of tying the NHL record set by Ottawa’s Ray Emery for consecutive wins to start a career.)

Not bad for a man who as recently as 2010 was teaching autistic students in a Swedish high school to supplement his night-time earnings playing in Sweden’s second division.

Fasth eventually advanced to the Swedish Elite League, where he remained on the radar of Ducks’ 15-year European scout, Jan-Ake Danielson.

Fasth’s elevation from Sweden’s second division, where he had a 2.15 goals-against average and league-best .930 save percentage, didn’t affect his results. Tutored by Swedish goaltending instructor Stefan Persson, he went on to collect two consecutive goaltender of the year awards in the Swedish Elite League. Yet, Fasth was never drafted by an NHL team.

Murray said Danielson pushed him to sign Fasth after the 2010-11 season, but Fasth was still under contract and his agent was seeking an NHL deal that would not permit a minor league demotion.

“I wasn’t going to go for that,” Murray said.

But Hiller’s past equilibrium issues and his workhorse effort convinced Murray that Hiller needed more rest to navigate a possible playoff run. With several other teams in bidding compensation for Fasth, Murray gave Fasth a $1-million no-minor-leagues contract.

“So far, so good,” Murray said. “For three straight years, I heard how Viktor was so calm and composed and nothing’s changed here.

“He remains very square to the shooters, always is very much in control out there with no wasted movement. He gives off that confidence, and the team sees that and feeds off it.”

Fasth said he was “excited” about that first meeting with Nashville a month ago and was confident despite not knowing what to expect about the faster tempo and higher skill.

“I trust my game,” Fasth said. “If I would doubt myself, there would be something wrong with me. I trust my game plan. I take that extra time in practice to be better in every part, and I rely on that knowledge I have when I’m playing.”

Fasth is giving up just 2.01 goals a game with the Ducks — eighth-best in the NHL. His eight wins are fifth best, even if he’s not considered the team’s No. 1 goalie.

“Coach talks to me and tells me if I’m playing or not,” Fasth said. “That’s how it works. You play when you’re told to play and try to do as good as you can.”

Tonight

VS. NASHVILLE

When: 7.

Where: Honda Center.

On the air: TV: Prime Ticket; Radio: 830.

Record vs. Predators: 2-0-0.

Update: The Ducks have beaten Nashville twice by shootout and the Predators lead the NHL with five losses in overtime or shootout.

lance.pugmire@latimes.com

twitter.com/latimespugmire