Ryan scored twice in the first period and completed his third career hat trick 30 seconds into the third. He later scored his career-best fourth point with an assist on All-Star pick Corey Perry's score during Anaheim's four-goal third period.
Ryan is embracing a major role in Getzlaf's absence with broken facial bones, shifting over from the wing to center Anaheim's top line. He has six goals in his last three games, including this barrage for his first career hat trick at Honda Center.
"It's special, because you're never going to get the hats [thrown on the ice] on the road," Ryan said.
Lubomir Visnovsky had a power-play goal while matching his career high with three points for the Ducks, who won three straight to wrap up a six-game homestand that catapulted them back into the Western Conference race. Anaheim's seven-game surge began on the same night Getzlaf was hit in the forehead by a deflected shot, likely sidelining him until next month.
"The month of December was a little bit ugly," Ryan said. "We've gone on streaks all year long. We need to come out at home, establish the forecheck, and establish our identity."
While coach Randy Carlyle knows he can count on Perry's consistency, he also sees Ryan maturing before his eyes. Already a proven NHL scorer at 23, the U.S. Olympian wasn't selected for the All-Star Game after struggling through a drought featuring three goals in 18 games before his current three-game outburst.
Carlyle said he uses "a three-pronged approach" to keep Ryan focused: video study, meetings and one-on-one coaching.
"He's got to feel good about himself," Carlyle said. "He can't be down. He's still a young player. It's nice to see that he's finally being rewarded in the last little while. ... He's a goal-scorer, and he scored goal scorer-type goals. The first two goals went off the post and in. Those are pretty fine shots."
Ryan clinched his third straight 20-goal season with a pair of nifty scores in the opening minutes while Anaheim went ahead 3-0. St. Louis dominated the second period while pulling within one goal, but the Ducks poured it on with four consecutive goals in the third.
Hiller's career-best shutout streak ended at 178 minutes, 34 seconds on Blues All-Star selection David Backes' first goal, but the Ducks' Swiss goalie earned his 22nd victory, matching Detroit's Jimmy Howard for the NHL lead.
Backes scored two second-period goals for the Blues, who are winless in five straight.
"You look at the start they got off to, they got a pretty good jump on us," Blues coach Davis Payne said. "We made some mental mistakes early that cost us. ... It's one thing not to have your legs going early, but the mental preparation has to be better."
Ryan Reaves scored his first NHL goal in the final minutes for St. Louis, which opened the second half of its regular season and a three-game California road trip by dropping to 0-4-1 in January.
"You've got to work your way out of it and be smart about it," Blues center Alexander Steen said. "We have another game [Thursday] against L.A., and we have to redeem ourselves. We've just gotten away from doing the little things right consistently throughout the 60 minutes."
Ryan scored during a power play just 3½ minutes in on a cross-ice pass from Joffrey Lupul. Ryan connected again on an exceptional pass from Perry, who fought off two defenders behind the net before finding Ryan in front.
Ryan nimbly deflected home Andreas Lilja's shot to complete the 30th hat trick in club history. Ryan has three of the last four, including two this season.
After Perry put a wraparound into an open net with 13:43 to play, the third period degenerated into a prolonged brawl that included six combined goals, 70 penalty minutes, four fights and two misconduct penalties.
- St. Louis D Carlo Colaiacovo was hit in the face by a puck off the stick of Anaheim's Matt Beleskey during the first period. He didn't return.
- Anaheim F Todd Marchant's third-period assist ended a 14-game scoreless skid for the former 60-point scorer.