"Having great goaltending," Boudreau said.
Devante Smith-Pelly scored his first goal in regulation since Halloween, then got the only goal in the shootout as Anaheim beat Los Angeles 4-3 Saturday night to take the West's top seed.
Anaheim will face Dallas in the opening round of the postseason.
"After having the time off that he did, it was important the he come in and play a real good game." Boudreau said.
It also leaves the coach with a difficult decision for the postseason. Play Andersen, who's recovered after missing three games with an upper-body injury, or go with fellow rookie John Gibson, who had a shutout last week and then got the win in the Pacific Division clincher?
Or just stick with veteran Jonas Hiller, who has struggled of late?
It's a good problem to have, even as Boudreau downplayed the significance of having home-ice in every series other than a potential Stanley Cup final against Boston.
"But I think if you get more in the habit of winning every day, it's harder to defeat you," Boudreau said.
The Ducks, who needed only a point to wrap up the top seed, got offense from an unlikely source.
Smith-Pelly, who has spent most of the season in the minors, scored his first goal in regulation since Oct. 31st to help his chances of making the postseason roster.
Anze Kopitar had two goals, including the tying one with 3:12 left in the third period, and Dustin Brown also scored for Los Angeles. The Kings fell short of getting their franchise-record 47th win in their regular-season finale.
The Kings are already locked into a first-round playoff matchup with San Jose.
"I think the last couple of games, definitely our intensity was there," Kopitar said. "Our intensity was there, our effort was there and that was obviously our preparation for the playoffs."
Both local rivals scored in the final 5 minutes of regulation, and Smith-Pelly then beat Jonathan Quick in the fourth round of the shootout.
"He bears down when he needs to," Boudreau said of Andersen. "The shootout was an example. Those guys made great moves."
The rivalry featured some oddities early: cheers for the opposition and a Kings penalty.
Los Angeles presented Anaheim winger Teemu Selanne with a paddle board before the game as he received a standing ovation from Kings fans. The retiring 43-year-old was in a suit as he had a scheduled night off before he's honored by his home fans in the regular-season finale Sunday against Colorado.
Brown put the Kings ahead less than 5 minutes in. Willie Mitchell retrieved an Anaheim turnover in the neutral zone and found Brown free at the blue line. He skated in alone and beat Andersen.
Bonino tied it less than two minutes later with an acrobatic goal. From his knees, falling away from the goal at a difficult angle, Bonino sent a backhander past Quick near the far post.
Brown was called for holding at 13:38, the first penalty against the Kings in three games and just over 140 minutes.
Both teams were 0-for-4 on the power play, while Quick made 21 saves.
"The building was loud, which was really nice to see," Kopitar said. "We are going to need that going forward. Now we have a couple days off to recharge."
Boston's victory over Buffalo earlier in the day ended the Ducks' chances of winning the Presidents' Trophy for the NHL's top record. ... Boudreau was noncommittal on whether he'll rest his key players Sunday against the Avalanche. ... Kings D Drew Doughty (shoulder) missed his fourth straight game.