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The 2017 NCAA Tournament has come to an end for Michigan, West Virginia, Purdue and Arizona. Kansas and Gonzaga, No. 1 seeds in their respective regions, have made it back to the familiar territory of the Elite Eight along with Oregon and, yes, Xavier, which knocked off No. 2 seed Arizona.

Thursdayâs games provided plenty of thrills, including one of the worst final possessions in NCAA Tournament history and a glimpse of a potentially legendary run from one of our No. 1 seeds.

How did the winners fare on Thursday night? Weâve got grades for each and a preview of whatâs to come.

61-58 over (4) West Virginia

For the most part, West Virginia played the game it wanted to play. Gonzaga turned the ball over 16 times, shot just 40 percent from the field and allowed the Mountaineers to grab 41 offensive rebounds. The Bulldogs were sped up by West Virginiaâs pace and out of sync on offense -- it was the kind of game that felt like a typical heartbreaking Gonzaga loss in the NCAA Tournament.

But this is not your typical Mark Few-coached Gonzaga team. Itâs been 18 years since the Zags first reached the Elite Eight, and now theyâre back with the best defensive team since Mark Few has taken over as head coach. Gonzaga does a tremendous job of playing help defense, denying the open space on the floor and forcing opponents to shoot over top from outside. Having that impact on the West Coast Conference is one thing, but having that stellar team defense show up again in the Sweet 16 is the mark of a champion.

West Virginia played the game it wanted to play and even led late, but after a big bag of onions from Jordan Matthews that defense won the game, forcing Jevon Carter and WVU into one of the ugliest final possessions in March Madness history.

73-71 over (2) Arizona

At one point this season, Xavier had lost six straight games. Entering the Sweet 16, they were the lowest seed remaining and the lowest-ranked team remaining in Ken Pomeroyâs rankings at No. 30. The Musketeers havenât had star point guard Edmond Sumner since Jan. 29 and many had written 2016-17 off as a lost season for Chris Mack.

Now Xavier is going to the Elite Eight for the first time since 2008, beating Sean Miller, the coach that took them to that Elite Eight.

Now Mack, the Miller assistant promoted after he left for Arizona, is one win away from his first Final Four and the hottest name on the list of potential candidates on the coaching carousel.

Mack drew up the perfect plays, gave the perfect instructions and Xavier closed better than anyone else on Thursday with a 12-2 run to close out one of the biggest wins in school history. Xavier led by eight with less than four minutes to go but played rock solid defense and denied both Allonzo Trier and Lauri Markkenen the opportunities they needed to power this Arizona team to a win. Brackets may be busted, but March Madness finally has the Cinderella its been waiting for int the West Region. Regardless of who wins on Saturday night between Gonzaga and Xavier, one team will be going to the Final Four for the first time in program history.

98-66 over (4) Purdue

The Jayhawks are at another level right now. There is no guarantee that theyâll win the national championship or even make it to the Final Four (more on Oregon, their competition for Saturday, below), but no one has looked more consistent through the NCAA Tournament than Kansas. It doesnât always look that way within the game, but by the end of 40 minutes itâs clear that most teams in college basketball just canât hang on their level.

Purdue actually led for 12 minutes during the first half, by as much as eight points with less than seven minutes to play before halftime, before the rug got pulled out from under the Big Ten regular season champions. Kansas big man Landen Lucas did a good job of denying Caleb Swanigan inside -- though Swanigan still finished with 18 points and seven rebounds -- and the Jayhawks turned every turnover and missed shot into an opportunity to get out and run in the open floor. Frank Mason III was in total Player of the Year mode with 26 points on 9-of-11 shooting with seven assists and seven rebounds, and Devonte Graham added 26 of his own thanks to five three-pointers.

By the end of the night in Kansas City, the building was chanting âRock Chalk, Jayhawkâ and Kansas had a new school record for the most points in its the first NCAA Tournament games. If this absurd pace continues, Kansas will threaten for a spot in the record books for most dominant Final Four runs in tournament history. But before the egg, we must talk about the chicken, or Duck...

69-68 over (7) Michigan

Michigan put on another typical second-half run, but Oregon, an experienced team thatâs now in the Elite Eight for a second straight year, did not wither. Ultimately the Wolverines fans will be kicking themselves for giving up offensive rebounds off missed free throws down the stretch, but Derrick Walton Jr. at least had a good look -- a step-back jumper, no different than any other huge shot heâs hit in clutch moments throughout his career -- to win the game.

Oregon got lucky here, and thankfully has Jordan Bell playing the best basketball of his career here in the NCAA Tournament. Bell shut down Michiganâs star sophomore Moritz Wagner and, pulled down key rebounds in the final minute that sealed the win. Tyler Dorsey continued his postseason tear with a team-high 20 points, but Bell was right there with 16 points to go with 13 rebounds and two blocks in the best performance of the evening for the Ducks.