Perhaps they weren't ready for primetime after all, this collection of very good players that Coach Ken Hitchcock nearly transformed into a President's Trophy winner.

Perhaps their impressive first-round win over the San Jose Sharks was an extension of their regular-season ownership of the teal and black. Perhaps the second-round adversity — injuries, veteran leaders unable to put goals on the board — overwhelmed them.

Or, perhaps, Jonathan Quick is just that damn good.

That last possibility is the most plausible one after watching Game 4 of the St. Louis Blues' Western Conference semifinal series, as Quick had his typical mix of athletic saves, timely stops and occasionally incredible good fortune. The Blues finally played an aggressive and impressive offensive game, and Quick was the difference, as the Los Angeles Kings won 3-1 and swept St. Louis out of the postseason.

Quick made 23 saves in the game, and stopped 96 of 102 shots in the series. He sent the Canucks home in Round 1, and it can be argued he's done the same with the Blues in the semifinals.

[Recap: LA Kings sweep St. Louis, advance to West finals]

That's the Kings' side of the equation; what went wrong with the Blues?

Injuries

Two injuries devastated the Blues in this series.

The first was losing Alex Pietrangelo in Game 1 on this Dwight King hit. He sat for Game 2, a 5-2 loss and a defensive disaster for the Blues. He returned in Game 3, but clearly wasn't the same effective player that he was during a Norris-caliber regular season. They felt his pain 5-on-5 and especially on special teams.

The second was losing Jaroslav Halak for the series after he was injured in the previous round. The Blues' two-headed monster in goal was the NHL's best in the regular-season, and there's no doubt Halak — a proven playoff performer, mind you — gets the nod on Game 3 had he been healthy.

Brian Elliott Is Human

Jeff Gordon of the St. Louis Post-Dispatch said it best: "With goaltender Jaroslav Halak sidelined by an ankle injury, his cohort Brian Elliott buckled under the full weight of his increased responsibility." That's a kind way of saying he had an .854 save percentage and inspired little in the way of confidence for his team against the Kings. The defense in front of him was porous, no doubt, but the "told-ya-so's" raining down from Ottawa must be reaching monsoon conditions.

The Power Play Stunk

The Blues posted six power-play goals in their first-round victory over the Sharks. Against the Kings' penalty killing, they were 0-for-17 (that includes a 1-second 5-on-3 in Game 4, for the record). Did Davis Payne coach the team in Round 2?

The Leaders Didn't Lead

David Backes tried to lead — putting up some offense while throwing the body around, but even he took a dumb penalty in Game 4. Still, the Blues' top players, overall, flopped in the semifinal round. Their top six had 10 goals and 15 assists against the Sharks, according to Bernie Miklasz of STLToday.com. They had 2 goals and 5 assists in four games against the Kings. Andy McDonald, Alex Steen and Patrik Berglund went from combining for eight goals against the Sharks to one goal from McDonald vs. LA.

T.J. Oshie finished without a goal in the playoffs. Jamie Langenbrunner and Jason Arnott were limited to one apiece. David Perron had two assists against the Kings but couldn't find the back of the net. The guys they needed to figure out Quick couldn't.

Overall, St. Louis Game Time summed it up:

The Blues are a strong team when they play a strong team concept game. That they have the right management in place in Doug Armstrong and the right coach in place in Ken Hitchcock. Much of the foundation is set - the team is a young core group and they all learned a lot of important lessons about how to win in the regular season and in the playoffs. They also learned how quickly it can be taken away.

So perhaps this had to happen, just like the Blues' last sweep out of the playoffs in 2009 had to happen for that young group. Or perhaps this was a team whose chemistry and cohesion was good enough to take them beyond the semifinals, but that simply fell apart against a Los Angeles Kings team that's starting to look a juggernaut thanks to their goaltender.

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