Just as St. Louis reached what's arguably been its season pinnacle to date, the hockey gods went and took something major away.

It'll be at least four weeks before No. 2 scorer Alexander Steen sees the ice again, and life without a top forward begins Monday night against the visiting San Jose Sharks as the Blues try to extend their season-best winning streak.

That streak reached five with Saturday's 6-4 win in Arizona, and Steen had a huge impact despite barely stepping on the ice. Steen quickly recorded a goal and an assist in just over two minutes of ice time then skated off holding his left arm, officially landing on injured reserve with an upper-body injury.

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"When our best all-around player goes down, there's a lot to shoulder," captain David Backes told the team's official website. "Different guys stepped up and played bigger minutes with bigger responsibility and did a heck of a job."

There's the consolation of getting goaltender Jake Allen back after sustaining a lower-body injury on Jan. 8 - he was activated Sunday - but that might only be an upgraded insurance policy given the way Brian Elliott has handled increased work. Granted, Elliott gave up four goals on 22 shots to the Coyotes, but he's gone 10-2-2 with a 1.70 goals-against average dating to Jan. 16.

One of those defeats came against the Sharks. St. Louis' last regulation loss came back on Feb. 4 to San Jose, going 6-0-1 since that 3-1 home loss. The Blues (35-17-9) have limited opponents to 12 goals in that time, and their penalty kill has gone 38 of 40 (95.0 percent) in nine games this month.

Offensively, the six-goal output matched a season high after topping out at two goals in nine of their last 12 games.

"You kept shaking your head and wondering if it was real," Backes said. "(Arizona) had 12 goals in their last two (games), and I don't know if we had that many in the last eight or nine.

"It was a wild ride, but we found another way to get another win and five in a row is a good feeling. Different guys are stepping up all the time."

Jaden Schwartz has been one of them with a goal in three straight games, and the forward has four goals and an assist in five games back from a fractured left ankle. The Blues are 10-2-0 with him on the ice this season.

San Jose (31-21-5) is out to bounce back from Friday's 5-2 loss in Carolina and win for the fourth time in five games as it continues a five-game road trip.

It was a rare road defeat for the Sharks, who had won eight of their previous 10 away games and are a win from matching their 2014-15 road win total of 21. It was also their third game in four nights, so two days off is probably much appreciated.

"We've been consistently good for a long time," said coach Peter DeBoer, whose team had allowed four goals on its preceding three-game winning streak. "You're going to have those once in a while. It's how we respond to it. I think we just have to throw it away and get ready for the next one."

The win in St. Louis at the beginning of the month featured a goal from Joe Thornton, who saw his seven-game point streak come to an end against the Hurricanes, but he has 11 on a six-game run against the Blues.

Martin Jones faced Carolina and St. Louis, posting a 1.58 GAA on a 4-1-0 span.