The UFC prides itself on being the world’s biggest MMA promotion. In 2021, we’ve seen some genuinely huge events already, headlined by fighters like Conor McGregor, Israel Adesanya and Francis Ngannou. However, that isn’t always the case.The UFC does put on some amazing headliners but, at times, the promotion also chooses to main event their shows with some much weaker fights.A number of things can be blamed for this – from the UFC spreading itself too thinly by putting on too many shows, to injuries forcing sudden changes. However, it’s safe to say that for UFC fans, there are few things worse than a weak UFC main event.With this in mind, here are five UFC main events that were hugely underwhelming.#5 Islam Makhachev vs. Thiago Moises – UFC Vegas 31Thiago Moises is an unlikely UFC main eventerWhen the UFC recently announced that their next visit to the APEX Centre in Las Vegas would be headlined by a lightweight clash between Islam Makhachev and Thiago Moises, most fans raised their eyebrows.Neither Makhachev nor Moises has ever headlined a UFC show before. To be fair, that’s obviously not an issue, as the UFC needs to push new headliners at times. But if we’re honest, the matchmaking here is bizarre at best.Makhachev is undoubtedly one of the best prospects in the UFC’s lightweight division now. He appears to be the promotion’s best chance of replacing Khabib Nurmagomedov as their big Russian star.After putting on a grappling masterclass Islam Makhachev forced Drew Dober to tap in the 3rd round! 👋The first man to greet and congratulate him? None other than Khabib! 🦅#UFC259 pic.twitter.com/CJ4oguqQUl— UFC on BT Sport (@btsportufc) March 7, 2021But why is he fighting Moises? The Brazilian is on a good three-fight win streak and is ranked at #14 in the division, but the way that Makhachev blew through Drew Dober at UFC 259 suggested it’s time for the Russian to take a step up in competition.Could the UFC really have not convinced Rafael Dos Anjos, Dan Hooker or Beneil Dariush – all of whom are ranked above Makhachev – to fight the Russian? Is Moises really the best they can do?This fight might turn out to be hugely entertaining, but right now it feels massively underwhelming considering what could’ve been put together for Makhachev’s next octagon appearance.Islam Makhachev vs. Thiago Moises will now serve as the main event of the UFC’s July 17 event, according to multiple people with knowledge of the agreement. Fight now scheduled for five rounds.— John Morgan (@MMAjunkieJohn) June 24, 2021