What former character played by Mark-Paul Gosselaar appeared on Late Night with Jimmy Fallon?

Mark-Paul Gosselaar just earned himself a spot in the late-night-interview hall of fame with Monday's appearance on Late Night With Jimmy Fallon. Sporting a preppy blond 'do, white hightops and acid-washed jeans and toting his huge cell phone, it was Zack Morris from Saved by the Bell who showed up to promote his alter ego Mark-Paul's TNT show, Raising the Bar—often by addressing the camera directly like a certain Bayside student we used to know and love. "I had to change my name to Mark-Paul Gosselaar because there was already a Zack Morris in SAG," Zack explained to Fallon, who strove to find out more about his guest's summer working at the Malibu Sands and his ill-fated marriage to Kelly Kapowski.

Then the actor committed to a class reununion (as did Jessie, via big, huge cell phone) and joined house band the Roots for a rendition of the Zack Attack classic "Friends Forever." Sources: