CHICAGO (AP) The lessons were difficult and painful. Three straight years of regular-season success for St. Louis, followed by playoff failure.
The Blues learned. They persevered, and they are roaring right now.
Vladimir Tarasenko scored on two dazzling wrist shots, Brian Elliott made 39 saves and St. Louis beat the Chicago Blackhawks 4-3 on Tuesday night to open a commanding 3-1 lead in their first-round playoff series.
''We just have a belief that we can beat anybody,'' Blues coach Ken Hitchcock said.
Jaden Schwartz scored a tiebreaking power-play goal in the third period for the second straight game as St. Louis moved one step closer to advancing to the second round for the first time since 2012. The Blues looked ready for deep playoff runs in each of the last three seasons only to be eliminated in the opening series each time.
Game 5 is Thursday night in St. Louis.
''There's a good feeling that we're more cohesive and playing for each other and doing the right things all over the ice than we ever had in this locker room,'' captain David Backes said, ''and that bodes well for our group.''
Duncan Keith had two goals for Chicago, which dropped consecutive home playoff games for the first time since 2012. Andrew Shaw had a goal and two assists, and Corey Crawford finished with 16 saves after getting into a fight with Blues rookie Robby Fabbri during a wild second period.
Shaw was sent off for interference at 17:56 of the third, hurting Chicago's chance for a comeback. While sitting in the penalty box, it looked as if Shaw directed a gay slur toward someone on the ice, and a gay rights group affiliated with the NHL said it planned to reach out to the league ''to assist in an appropriate response.''
''Emotions are high. I don't really know what's said,'' Shaw said when asked about what happened. ''Like I said, I was obviously upset with the call. Being that late in the game, it doesn't give us a chance to tie it up.''
With Keith in the box for holding Alexander Steen, Schwartz intercepted a clearing attempt by Blackhawks defenseman Trevor van Riemsdyk and beat Crawford low on his stick side at 1:36. Schwartz had the game-winning goal in St. Louis' 3-2 victory in Game 3 on Sunday.
Steen then picked off a pass by van Riemsdyk and went in all alone on Crawford for his first goal of the series at 4:46, stunning the sellout crowd of 22,212.
''Steener getting that unassisted breakaway was a huge play for us,'' Elliott said.
A fortunate bounce for Keith off Tarasenko's stick and over Elliott gave the Blackhawks some hope, but Elliott shut the door from there.
Before Schwartz and Steen broke through, it was the Tarasenko show once again for St. Louis. The dynamic wing has three goals and two assists in the series and 13 goals in 17 career playoff games.
The Blackhawks had a 2-1 lead and momentum before Andrew Ladd was penalized for interference at 17:09 of the second. Just 22 seconds later, Tarasenko whistled a shot under Crawford's glove for the tying score.
''I don't know how he shoots the puck like that,'' Backes said. ''I wish he'd tell me his secret. But he's a talent.''
Tarasenko's goal capped a frenetic second period that included a fight between Crawford and Fabbri after the forward was pushed into the goaltender on a rush to the net. Crawford skated into the corner and shoved Fabbri before the two wrestled on the ice.
The crowd responded with chants of ''Co-rey! Co-rey!'' and the resulting fracas between the teams somehow generated a power play for the Blackhawks. Fabbri (interference), Alex Pietrangelo (roughing) and Kevin Shattenkirk (roughing) were sent off for St. Louis, and Crawford (roughing) and Ladd (roughing) were penalized for Chicago.
''I felt like I got pushed from behind and I tried to do my best to fall away from him,'' Fabbri said. ''I guess he didn't like that.''
Crawford said he doesn't remember too much about what happened but he was angry after he got hit in the head.
There was another big fight between the teams right after the final horn, and there were 140 penalty minutes assessed for the night.
During the power play after the Crawford-Fabbri dispute, Keith scored on a rebound to give the defending Stanley Cup champions a 2-1 lead at 13:09. The defenseman has three goals in the series after winning the Conn Smythe Trophy as playoff MVP a year ago.
NOTES: Blues D Carl Gunnarsson was scratched with an upper-body injury. Robert Bortuzzo replaced him in the lineup. ... Blackhawks D Erik Gustafsson returned to the lineup after he was scratched in the previous two games. F Andrew Desjardins also played after he was inactive for Game 3. ... Steen had an empty-net goal in the final minute disallowed by an offside call.
Jay Cohen can be reached at http://www.twitter.com/jcohenap