Sean O'Malley became the UFC bantamweight champion this past weekend and it seemed destined right from the get-go that he'd eventually wear gold. But that's not always the case. While O'Malley was a hype train in that he was clearly backed by the UFC promotional machine and got beneficial matchups at times, there are many other hype trains that end up getting derailed, sometimes in spectacular fashion.

However, in some cases, the UFC strikes gold and certain hype trains live up to their potential and end up becoming champion. So following UFC 292, here are five hype trains that eventually became UFC champion.

Sean O'Malley

It's fair to say the UFC were all in on Sean O'Malley right from the moment he delivered that highlight-reel knockout on the Contender Series. Since then, O'Malley has slowly risen the ranks with impressive wins, but mostly over unranked opponents in three-round fights. “Sugar” claimed he had no interest in fighting higher-level opponents in five-round fights until his contract made it worth it. Because of this, many felt O'Malley was purely all hype and no substance as he wasn't facing the elite nor was he getting tested on the ground by a high-level wrestler or grappler.

There were setbacks along the way too, such as his various ankle and leg injuries, especially against Marlon Vera which resulted in his first-ever defeat, that led many observers to believe he'd never become champion. However, O'Malley bounced back and shocked many with his performance in a split decision victory against former champion Petr Yan. Although the consensus is that Yan won, it was still an extremely impressive performance that showed O'Malley could hang with the top. It eventually earned him the shot at Sterling and the rest is history. Nobody is calling Sean O'Malley a hype train anymore.

Jiri Prochazka

It might seem odd to mention Jiri Prochazka on this list, but he was a hype train in that he entered the UFC with plenty of excitement as a former RIZIN champion. Not to mention, he was given a fast-track to a light heavyweight title shot with just two wins in the UFC. To his credit, those were two very impressive wins as he knocked out former title challengers Volkan Oezdemir and Dominick Reyes in emphatic fashion.

He would face veteran champion Glover Teixeira last year and it turned out to be a Fight of the Year candidate in a back-and-forth brawl that eventually saw Prochazka earn the late fifth-round submission. Unfortunately, he had to vacate the title soon after as he required shoulder surgery, but he should be back in action soon for the currently-vacant 205-pound crown.

Khabib Nurmagomedov

Former UFC lightweight champion Khabib Nurmagomedov wasn't a hype train in the sense that he was backed by the UFC right from the get-go like an O'Malley. However, it became very clear that the Las Vegas-based promotion were all in on him following his impressive UFC 205 win over Michael Johnson and subsequent callout of Conor McGregor. In fact, the hype was real with the Dagestan native well before that night given his dominance and unbeaten run.

Although he missed weight for his UFC 209 interim lightweight title matchup with Tony Ferguson in March 2017, Nurmagomedov fixed things upon his eventual return where he dominated Edson Barboza before defeating Al Iaquinta on short-notice for the vacant lightweight title. Some still felt he had a padded record at the time, but given that he went on to comprehensively defeat the likes of Conor McGregor, Dustin Poirier and Justin Gaethje as champion, it's safe to say the now-retired Nurmagomedov has nothing further to prove.

Israel Adesanya

Israel Adesanya was another fighter that arrived with plenty of hype as he was a high-level kickboxer. He was also a unique hype train in that he was extremely active and fought pretty good competition along the way. After all, he was fighting Derek Brunson in just his fourth UFC fight.

He would eventually fight Kelvin Gastelum in a back-and-forth war for the interim middleweight title and come out on top in a fight that showed he could truly dig deep. It still remains the most damage he's ever taken at middleweight as a whole. That win set up a meeting with Robert Whittaker where Adesanya simply outclassed him with a second-round knockout victory to become UFC champion. Although he would later lose the title to Alex Pereira (an honorable mention for this list), Adesanya would regain the title soon after and become a two-time champion. In fact, he has been involved in every middleweight title fight since Gastelum. That's well over four years of dominance.

Conor McGregor

Of course, the biggest hype train in recent memory is probably Conor McGregor — and he lived up to it in more ways than one. With a brash and confident attitude, charisma for days and knockout finishes, the Irishman seemed destined for UFC glory. Of course, many weren't convinced along the way as they felt he was all talk and yet to face high-level opposition (or wrestlers). He was even granted a title shot off a win over Denis Siver.

However, legendary featherweight champion at the time Jose Aldo was injured which led to McGregor facing the tough Chad Mendes on short notice for the interim title. McGregor's wrestling would be tested this time and although he was taken down and bloodied by Mendes, he eventually got back to his feet and managed to knock him out. He got past a high-level wrestler. Still, there were doubts over McGregor as Mendes stepped in on short notice and didn't have a full camp. Everyone was sure that Aldo would be the one to expose McGregor. As we all know, all it took was 13 seconds.