11 WWE Rivalries That Defined The 2000s
8. Kurt Angle Vs. Brock Lesnar

As soon as The Next Big Thing signed with the then-WWF in 2000 (for $250,000 downside per year, a record sum for a developmental talent), company officials were no doubt eagerly anticipating the day they could book him against Kurt Angle.
Both were amateur wrestling standouts, with Lesnar being an NCAA Division 1 Heavyweight Champion and Kurt Angle being an Olympic gold medalist (which he accomplished with a broken freakin' neck, in case you hadn't heard). WWE knew it'd be a huge match and saved it for the biggest occasion.
The first time the two locked horns in a singles match was in the main event of WrestleMania XIX. There, the two put on an absolute pure wrestling clinic, which is amazing given Angle's perilous physical condition at the time as well as the fact that Lesnar very nearly did himself in on a Shooting Star Press gone wrong.
The two would engage in a friendly rivalry/partnership upon Angle's return from neck surgery in the summer, which lead to Lesnar turning heel so they could run the match again only this time with the roles reversed.
The Next Big Thing and the Olympic Hero had two more standout matches at SummerSlam and then in a rare 60-Minute Iron Man match on Smackdown. They didn't have a great deal more interaction with each other, but their WWE Title rivalry built on pure competition made for some gripping television.