NBA playoffs 2018: Who are title contenders?

CLEVELAND, OH - JUNE 09: Kevin Durant #35 of the Golden State Warriors competes for the ball with Tristan Thompson #13 of the Cleveland Cavaliers in the second half in Game 4 of the 2017 NBA Finals at Quicken Loans Arena on June 9, 2017 in Cleveland, Ohio. NOTE TO USER: User expressly acknowledges and agrees that, by downloading and or using this photograph, User is consenting to the terms and conditions of the Getty Images License Agreement. (Photo by Ron Schwane - Pool/Getty Images)

(CNN) — A year ago heading into the NBA playoffs, fans were preparing for Cavs-Warriors III in the NBA Finals, which ended with Golden State winning its second title in three years over Cleveland.

This season, though, Cavs-Warriors IV is not a guarantee.

The playoffs have clear-cut championship contenders — both from the Western Conference — and teams from the Eastern Conference that are in the hunt.

Here is a look at those groups:

Leading contenders

Houston Rockets

Any lingering questions if stars James Harden and Chris Paul would play well together have been answered. It’s a resounding yes, they do.

When Paul — who was acquired by Houston from the Los Angeles Clippers in the offseason — and Harden are both in the lineup, the Rockets have dominated, and they appear to be on a collision course with Golden State in the Western Conference finals.

There’s already one item in the Rockets’ favor: They have home-court advantage for the Western Conference playoffs by earning the top seed.

The prevailing view for most of this season had been that the Warriors can win a seven-game series on the road if necessary. However …

Golden State Warriors

… While the Warriors’ lineup is packed full of stars, there is reason to worry: injuries. Stephen Curry has had ankle and knee problems, and head coach Steve Kerr has said he’s ruling him out of the first round.

Additionally, Kevin Durant, Klay Thompson, Draymond Green and Andre Iguodala all have missed games because of varying maladies.

The Warriors undoubtedly are a favorite to reach the NBA Finals, which would make it the fourth consecutive season. But their run is in jeopardy.

In the hunt

Toronto Raptors

The Raptors are having their finest season in franchise history and could be the team to beat in the East. They’ve also been healthy, with the core of DeMar DeRozan, Kyle Lowry, Serge Ibaka and Jonas Valanciunas and the young guys supporting them meshing well.

Historically, Toronto has underperformed in the playoffs. The one time the Raptors reached the Eastern Conference finals, in 2016, they got blown out by the Cavaliers. Provided it doesn’t regress to old playoff form, Toronto is poised for a breakthrough.

Boston Celtics

The Celtics’ season looked doomed from the opening minutes when Gordon Hayward suffered a gruesome fracture dislocation of his left ankle. Turns out that was far from accurate, as evidenced by their 16-game win streak early in the season.

But there are still question marks. Star player Kyrie Irving, acquired in a blockbuster trade from Cleveland last summer, had a procedure March 24 to remove a tension wire in his previously surgically repaired left knee. Irving’s estimated time away was listed at three to six weeks.

If Irving is not available, can the Celtics win? Even if he plays, it’s tough to see the Celtics getting out of the Eastern Conference at this point.

Cleveland Cavaliers

It of course helps when you have arguably the NBA’s best player, LeBron James, who is looking to return to the NBA Finals for the eighth consecutive year (and ninth overall). But it’s been an unsteady year for Cleveland.

The question is how the Cavaliers will respond in the playoffs after a roller coaster regular season. They can score, but their defense hasn’t been good. How will they hold up against playoff teams?

Just four players remain from Cleveland’s title team from 2016: James, Kevin Love, JR Smith and Tristan Thompson. Within this season, the roster has had an overhaul, trading several players, including Dwyane Wade, Isaiah Thomas, Jae Crowder, Derrick Rose and Iman Shumpert.