JDS/Werdum and it's not close
Fab was a top 5 HW behind Fedor, Nog, Josh and Andrei. He was arguably the UFCs best HW at the time considering the Arlovski fight was pretty close statistically but Werdum was flopping a lot. He was on the cusp of a title shot and got murked by the uppercut
JLau/Pulver deserves an HM
Even tho he lost I'd put Landos debut up there maybe top 5. That's the closest Tony has come to being finished in UFC, and Lando gave us arguably round of the year and one of the best FOTY
Dustin beating 14-1 Grispi who was #1 contender and supposed to fight Aldo for the title. It was both of their debuts post WEC merge
Also Reem destroying Bork in his debut too