6. Jose Aldo
One of the most hated rivalries the UFC has ever seen was between Conor McGregor and Jose Aldo, as the two men traveled the world together for nearly a year to promote their clash for the featherweight title, time that McGregor used to get under the skin of ‘Scarface’.
McGregor and Aldo were originally set to clash in the main event of UFC 189, being ‘Notorious” first shot at a UFC title in his short career with the promotion. Unfortunately for McGregor, however, Aldo would be forced to pull out of the contest citing an injury sustained in training camp, opening up the door for Chad ‘Money’ Mendes to step in and challenge McGregor with an interim title being placed on the line.
Mendes would eventually fall to McGregor’s left hand in the second round of the contest, where a unification bout between McGregor and Aldo for the two featherweight titles would be put into place for UFC 194. When the two finally squared off it took McGregor only 13 seconds to land his powerful left had shot on Aldo’s chin, who took advantage of the overly emotional Brazilian, taking away his decade long undefeated streak and featherweight crown with one deadly swing.
Since then Aldo has returned to the Octagon to capture an interim featherweight title of his own, campaigning hard for a shot at redemption against the brash Irishman. His efforts, however, have proven unsuccessful as of late, but with McGregor finally accomplishing his longtime goal of becoming a dual-weight UFC champion perhaps the door has opened for a featherweight title defense against Aldo next.