The struggling Toronto Maple Leafs have fired head coach Mike Babcock.

Leafs president Brendan Shanahan announced Wednesday that Babcock had been relieved of his duties and that AHL Toronto Marlies coach Sheldon Keefe has been named the club's new head coach.

Shanahan, who hired Babcock in 2015, flew to Arizona on Wednesday to break the news along with general manager Kyle Dubas.

"It wasn't an easy conversation to have and it wasn't pleasant, days like today are not," Shanahan said in Scottsdale, Arizona. "But it was what we felt was important for the club. Once you realize there's something you should do, and have to do, then it's best to act on it."

Toronto has been one of the NHL's biggest disappointments this season, stumbling to a 9-10-4 record. The Leafs have just one regulation victory since Oct. 26, and are in the midst of a six-game winless streak that features five losses in a row -- including Tuesday night's 4-2 defeat at the Vegas Golden Knights. It was Toronto's second game of a six-game road trip, and apparently was seen as a critical stretch by management.

"I'm disappointed," Babcock said in a statement to TSN. "We didn't have the start to the year we wanted and that's on me. I want to thank the fans. I want to thank the media. I want to thank the city.

"It was spectacular. I loved every second of it. And I wish the new group nothing but success. Morgan Rielly has been here the whole time. I can't thank him enough. And all the players I got an opportunity to coach, it's been fantastic and I wish them nothing but success."

Babcock has a career record of 700-418-19-164 with the Mighty Ducks of Anaheim, Detroit Red Wings and the Maple Leafs. He won the Stanley Cup with the Red Wings in 2008, and he returned to the Final the following season before losing to the Pittsburgh Penguins.

He was hired by Toronto in May 2015, after stepping down from Detroit, and reportedly signed an eight-year contract worth $50 million to become the highest-paid coach in NHL history at the time.

After missing the playoffs in his first season, the Leafs reached the playoffs for three straight years but failed to advance out of the first round -- falling to the Washington Capitals in 2017 and the Boston Bruins in 2018 and 2019.

"I thought we did an amazing job taking a franchise from where it was to where we had 100-point seasons, we set franchise records, if I'm not mistaken, [and] got into the playoffs," Babcock said.

This season has been a dud so far for the Leafs. Injuries to center John Tavares and winger Mitch Marner were a factor, but the team's offense (3.14 goals per game) could no longer compensate for its porous defense (3.43 goals against per game). The Maple Leafs had the sixth-best combined record in the NHL over the previous two seasons with a .625 points percentage. This year, they ranked 25th (.478) heading into Wednesday.

"Our game is not really meeting our expectations," Shanahan said Wednesday. "We're mistake-prone on defense, the attention to details aren't there, and even the explosive offense that our team was known for has been missing for a while now, so there's a lot of work for Sheldon to do and there's a lot of work for the players to do."

Keefe, who has long been considered the heir apparent to Babcock, coached for Dubas with the Soo Greyhounds in the OHL, and he was hired by Dubas in June 2015 to coach the Marlies. The 39-year-old Keefe, a former NHL player, led the Marlies to at least the second round of the playoffs in each of his seasons there, and he won the Calder Cup in 2018.

Babcock is one of seven head coaches in NHL history with at least 700 victories. In the first eight seasons of his head-coaching career, he made three Stanley Cup Final appearances and his team finished first or second in their division seven times. In the next eight seasons, his teams never finished higher than third in their division.

Despite all of the disappointment and controversy, the Leafs sit just two points out of the last wild-card spot in the Eastern Conference, although the Philadelphia Flyers have two games in hand.

The firing of Babcock arrives on an interesting anniversary: The St. Louis Blues fired head coach Mike Yeo on Nov. 20 last year, turning their season around under new coach Craig Berube and eventually winning the Stanley Cup.

The Associated Press contributed to this report.