Who was the champion before your rival in the first generation Pokemon games?

When you beat the elite four, there's always a champion. when you beat that champion, you become the new one. In the Red and Blue (and yellow) your rival had JUST become the champion before you beat him. So, who did he have to beat? And if it's Lance, then who was the other elite four member that Lance stepped in for?|||Not to sound rude, but it does not say because it is not relevant to Ash's story. Interesting, though, I had never thought about it.