#1 Royal Rumble 2004: Chris Benoit became the first cross-brand challenger

Even though the odds were stacked against him, Chris Benoit won the Royal Rumble after entering at the first position in the match. He became only the second man in WWE history to win this coveted match from that position and clocked the time of over 61 minutes.
Chris Benoit faced the champion, Triple H, and Shawn Michaels in a Triple Threat Match in the main event at WrestleMania 20, and became the new World Heavyweight champion.
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Historical Impact:
SmackDown's General Manager, Paul Heyman, had a strong disliking for Chris Benoit. He vowed before the Royal Rumble PPV that Benoit would never become a World Champion.
Notably, the rules of the Royal Rumble match didn’t state clearly that which brand’s champion the winner should challenge. It was a norm for the winner to choose the champion of their respective brand. However, the Rabid Wolverine was able to figure out this loophole in the rules.
After winning the match, Chris Benoit appeared on Monday Night Raw the following night and announced that he would face the World Heavyweight Champion at WrestleMania 20 instead of facing the SmackDown's WWE Champion.