It sounds like Undertaker would have preferred losing his WrestleMania undefeated streak to Roman Reigns instead of Brock Lesnar.
Undertaker WrestleMania dream match
I Wanted to Save It: 'American Badass' The Undertaker Confessed the Biggest Regret of His WWE Career in Heartfelt Out of Character Talk with Stone Cold Steve Austin - EssentiallySports
4-Time WWE Champion Shoots on Brock Lesnar for Ending The Undertaker's Streak: “Put That Huge, Neon-Flashing Sign” - EssentiallySports
On April 6, half a decade ago, Brock Lesnar ended The Undertaker's WrestleMania streak. Becoming the 1 in 21 and 1. : r/SquaredCircle
21-1 Unbreakable
Jake Roberts Believes WWE Wasted Undertaker's Streak On Brock Lesnar: He Didn't Need That Push
WWE: Undertaker says Roman Reigns, not Brock Lesnar, should've ended streak - Sports Illustrated
WWE's The Undertaker reveals the locker room reaction to the end of his WrestleMania streak
Undertaker On If He Thought The Streak Ending Was a Mistake, Says He Double-Checked With Vince And Went With It
Was Brock Lesnar the Right Guy to End The Undertaker WrestleMania Streak?
WWE WrestleMania: How The Undertaker reacted to being told Brock Lesnar was ending his streak
The Undertaker reveals he was going to beat Brock Lesnar at WM30 before Vince McMahon changed his mind ON THE DAY and broke the streak