The Stars announced Sunday that Lindy Ruff will not return as head coach for the 2017-18 season.

Ruff's four-year contract expires at the end of this season and he will not be offered an extension.

The Stars will immediately begin the search for Ruff's replacement. Here are three candidates to consider:

Ken Hitchcock

File photo/Illustration by The Dallas Morning News

Yes, the Stars could bring back the most successful coach in franchise history. Hitchcock was let go by St. Louis this season, and is available. Many believe the 65-year-old might be ready to retire, but the lifetime coach pulls too much energy from his job to do that. If he is asked, the guess here is that Hitchcock would be interested.

But is he the best man for the job?

Maybe the most significant criticism of the Stars through Marc Crawford, Glen Gulutzan and Ruff is the lack of defensive structure. The team has been able to score, but it has given up way too many goals.

Hitchcock's main strength is defensive structure. He, in fact, will hammer his players with details and defense until they either become very good or revolt. That's one of the reasons he is third all-time in coaching wins and is looking for his fifth head coaching gig.

Hitchcock had a .650 winning percentage in six seasons with the Blues, and yet still was let go mid-season. That's the way things work with the NHL merry-go-round. Randy Carlyle returned to Anaheim and has the Ducks back in the playoffs. Claude Julien seems like the perfect answer in his return to Montreal. Mike Yeo left Minnesota and is having success as Hitchock's replacement in St. Louis. The league feels changing the voice is a good thing, and Hitchock would definitely be a significant change.

Because of his age and love of coaching, he would probably take a shorter term contract. Because of his age and style, he would probably be the best bet for an immediate turnaround and the most risk if you are interested in a more long-term answer.

It would be a statement hire that the time for winning is now.

And the one intangible Hitchcock would bring is he very much loves this franchise. He got his start here, he built a lot of the fan base here, he still has a lot of friends here. It would mean a lot for him to restore the glory of the Stars.

Gerard Gallant

Photo by Getty/Illustration by The Dallas Morning News

When Bob Gainey first built the Stars, he did it on the connections he made while a player in the NHL. They called Dallas "Montreal South" at the time, and with good reason. From assistant coach Doug Jarvis to players like Craig Ludwig, Guy Carbonneau, Brian Skrudland, Mike Keane and Kirk Muller, Gainey relied on the trust he had in old friends.

Gallant and Jim Nill played together in Detroit, and he might be the most comfortable head coach the GM could select.

Gallant has coached parts of six seasons with Columbus and Florida and has accumulated a 152-141-35 record. He led the Panthers to a division championship last season and seemed to have everything moving in the right direction when new leadership decided he wasn't the answer early this season.

Gallant was awkwardly fired on the road and has become something of a sympathetic figure in the NHL. Not only did Florida management look bad for letting him go, the team still missed the playoffs and will now be looking for a new coach again.

Gallant was criticized for not being more into analytics by the men who fired him, but he coached a simple game that got results. It is low-event hockey, as only the New Jersey Devils had fewer shot attempts last season than the Panthers. Florida finished 29th in SAT (shot attempts at even strength) at 3,105 and had the fourth fewest shot attempts against.

That said, it also ranked seventh in goals against at 2.44 and seventh in save percentage at .917.Meanwhile, it ranked eighth in scoring at 2.83 goals per game, while having the 24th best power play.

You can say those numbers aren't sustainable, as the Panthers were fifth in shooting percentage at 9.8 percent, but there is something to be said for a counter-attack system that creates offense out of defense.

Gallant is 53, so he could be a coach that could be here for a while if he succeeds. He has been an assistant coach with the Blue Jackets, Islanders and Canadiens, and helped the 2013-14 Canadiens to the Eastern Conference finals, so he has plenty of NHL experience.

He is seen as a player's coach and he knows the GM pretty well, so that makes him an appealing option.

Kirk Muller

Photo by Getty/Illustration by The Dallas Morning News

While Hitchcock and Gallant are available now to be hired, the Stars would have to show patience with Muller. One, he is currently employed as the associate coach with the Montreal Canadiens and could have a long playoff run in front of him. Two, his name is being bandied about as a candidate to be the first head coach of the Vegas Golden Knights, so there could be a bidding war whenever his season ends.

There's good reason for that. Muller is seen as one of the bright offensive minds in the NHL, and many believe he is the kind of coach who can connect with the young speedy players who seem to be the next wave.

Muller was an outstanding offensive player in his day, tallying 959 points in 1,349 games. He was the second overall pick in 1984 (New Jersey) and helped Montreal win the Stanley Cup in 1993. He then converted to a defensive forward and finished out his career with the Stars, helping them to the Stanley Cup Final in 2000.

So he knows both sides of the game.

Muller had a three-year stint as head coach of Carolina from 2011-14, but he has found success more recently as an assistant and associate coach. Muller ran the Blues' power play, finishing fourth and sixth in his two seasons there. He has Montreal 13th on the power play this season, but there is the belief he would have even more talent to work with in Dallas.

The Stars have some offensive firepower in Tyler Seguin, Jamie Benn and Jason Spezza and could have two great power play quarterbacks in John Klingberg and Julius Honka. Could Muller continue the offensive style that has been created here and then add a defensive twist to it? Could he be combined with a veteran defensive assistant who could help team the young blueliners?

It's a theory that could work. But it has risks, including the fact you have to wait for Muller to be available. If you do that, could you miss on a pretty good bird in the hand?