#4 Braun Strowman

Braun Strowman was rumored to be The Undertaker's WrestleMania opponent in 2017 at one point. However, it was Roman Reigns who ended up taking that spot (becoming only the second man to beat The Undertaker at WrestleMania).
While there was little chance of Strowman ever beating The Undertaker, there's no doubt that at the time, he was extremely deserving of having that match. He was the hottest Superstar in WWE in early 2017 and his momentum even spilled onto 2018 despite suffering a couple of big losses to Roman Reigns early in 2017 and Brock Lesnar later in the year.
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It would have been the perfect time to pull the trigger on him and elevate him, but the running theme of WWE's main event scene was their push of Roman Reigns, which involved compromising other wrestlers and their momentum.
Strowman essentially suffered the same fate as Jon Moxley/Dean Ambrose did in 2016, but it took him a few more years to become Universal Champion. Still, it's a shame that we never got to see this dream encounter between the two big men.
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