On Wednesday morning, Blues General Manager Doug Armstrong announced that Ken Hitchcock was relieved of his duties as head coach. Yeo, who was hired last summer as the team's associate coach and was to take over following Hitchcock's final season, was promoted effective immediately.

In addition, Goalie Coach Jim Corsi was also relieved of his position. Assistant GM Martin Brodeur and Goalie Development Coach Ty Conklin will share those duties.

"We made a lot of hard decisions last summer, and the decisions were made with not just this season in mind, but the future of the franchise in mind," Armstrong said during a press conference Wednesday, referencing the club's offseason losses of David Backes, Troy Brouwer, Steve Ott, Brian Elliott and coaches Brad Shaw and Kirk Muller. "I don't think we've given our best effort and ultimately Ken is paying the price for all our failures, starting with mine."

"It just felt like we were hit and miss night in and night out," Armstrong added. "We need to demand more of ourselves, and our record is not indicative of what we thought (it would be)."

Video: Armstrong, Yeo hold press conference

Armstrong's decision comes as the Blues have lost five of their last six games and finished 5-8 during the month of January. With a 5-3 loss to the Winnipeg Jets at home on Tuesday night, the Blues now find themselves in the final Wild Card position in the Western Conference.

After starting the season 15-7-4, the Blues are 9-14-1 since.

"The first thing I have to do is thank Hitch," Yeo said. "He was nothing but amazing to me, day in and day out. I learned a great deal from him and I'm very appreciative. I feel extremely bad that I'm sitting up here (for this press conference) today. That said, I know that I have a job to do, a very important job to do, and one that I don't take lightly. When I look at the people that have coached the St. Louis Blues, and Hitch being one of them, those are some awful big shoes to fill. And I look forward to that challenge. I look forward to working with this group (because) it's a group I believe in. I know there's lots of work to be done, but I'm excited to work with them and I'm ready for that process to begin.

"None of us are satisfied or can be satisfied with where we're at right now," Yeo added. "We all have to dig much, much deeper than what we have."

Hitchcock served as the head coach of the Blues since Nov. 8, 2011. Over six seasons, he led the Blues to a 248-124-41 regular season record and ranks second on the Blues' all-time regular season wins list and fourth in NHL history overall with 781 career regular season wins. Only Alex Pietrangelo, Alexander Steen, Patrik Berglund, David Perron and Ryan Reaves remain from the team in 2011 when Hitchcock was originally hired.

Video: Players react to coaching change

"There's one guy in that room, or one former guy in that room, that I think is going to the Hall of Fame and it's Ken Hitchcock," Armstrong said of his former coach. "Maybe some of those other guys will get there, but they've got a long way to go to reach the standard that he's set… He's leaving this group in a way better spot than he found it."

Yeo is in his first season with the Blues after spending the majority of his career as the head coach of the Minnesota Wild. Yeo led Minnesota to a 173-132-44 record, which included three consecutive postseason appearances, including back-to-back appearances in the second round in 2014 and 2015. Prior to his stint in Minnesota, Yeo spent one season as the head coach of the American Hockey League's Houston Aeros, where he led the club to the 2011 Calder Cup Final.

Yeo also spent 10 seasons in the Pittsburgh Penguins organization, including four as an assistant coach with the Penguins, where he captured the 2009 Stanley Cup.

"There's not going to be, come tomorrow night, (any) major personnel shuffles," Yeo said. "I think what's important is we give the players a chance to go out there and show us what they can do… We can determine a little more of the chemistry once we get our game going in the right direction.

"Our game, for whatever reason, is not where it needs to be right now... I wanted to turn it around as an assistant coach and that didn't happen, and now I have to do it as a head coach."