Ducks enforcer George Parros tried to fight Janssen, but Janssen didn't oblige, and Parros got an unsportsmanlike conduct penalty that led to a St. Louis power-play goal.
"I didn't have any problem with the hit, but the fake of the dropping of the gloves for a player of that stature and his job," Ducks coach Randy Carlyle said. "Think about it. What would your answer be to it.
"Really, I think what happened was after the penalty to George, on the Janssen incident, we got emotionally involved in the game. That was the difference. If he (Janssen) thinks he did the right thing, well, he just stirred our group."
"Tonight, we found a way to win one and that's a good sign," Carlyle said.
Ryan's goal at 12:49 of the third period gave Anaheim a 4-3 lead. He backhanded a shot off the near post off a feed from Scott Niedermayer for the Ducks' second power- play goal of the game.
"They told me where to be and pucks were going to find me in there with Scotty walking off the half wall so I was just patient," Ryan said. "Sure enough, it came and I was able to poke it into an empty net. I think (Blues goalie Chris Mason) probably lost it in the scrum there."
The Blues took their first lead of the night on Boyes' team-leading 17th goal of the season, a power-play strike at 6:41. It came following Parros' unsportsmanlike conduct penalty trying to get Janssen to drop the gloves, but the Ducks tied it 37 seconds later on Montador's second of the season, a slap shot from the blue line.
"I didn't like (Montador's goal) because Cam Janssen went on the ice and did his job, finished a check, took a punch in the back of the head, didn't retaliate, drew a penalty (and) we score on a power play," Blues coach Andy Murray said. "We put out our stopper unit and we get scored on. It shouldn't happen."
The Ducks opened the scoring at 1:41 of the first on Rob Niedermayer's eighth goal of the season. He beat Mason off a rebound.
Perron tied it for the Blues at 5:01 of the first with an unassisted goal. He gained control along the right boards and snapped a shot between Hiller's pads.
The teams also traded goals in the second period, with the Ducks going up 2-1 on Scott Niedermayer's power-play goal at 4:16 off Getzlaf's feed from the left circle. The Blues tied with a power-play goal of their own, Tkachuk's 13th of the season at 16:22. He redirected Berglund's shot from the top of the right circle.
David Backes had a chance to tie it in the waning seconds for the Blues, but his shot from the slot was kicked out by Hiller.
"Rebound on my tape, (the puck) just kind of on its side and (Hiller) gets the pad on it," Backes said. "I don't get it up and the game ends in the wrong direction."
- Thachuk's power-play goal was his 86th for the Blues, tying him for fourth on the team's career list with Garry Unger. Tkachuk has nine-power play goals this season, good for sixth in the NHL.
- Both teams played Saturday that required extra time. The Ducks fell 4-3 in overtime at Dallas, while the Blues beat San Jose 3-2 in a shootout.
- Ducks C Brendan Morrison has four goals in the last three games, doubling his season output after scoring four goals in his first 33 games.
- Perron has goals in consecutive games after scoring two in his first 33.