Photo gallery: The many weights of UFC 205 headliner Conor McGregor

Tonight at UFC 205, featherweight champion Conor McGregor not only looks to make history as the first simultaneous two-division titleholder in UFC history, but he also hopes to join an elite group of fighters who have earned octagon wins in three weight classes.

Only six fighters in the promotion’s existence have registered wins in three divisions, and McGregor (20-3 MMA, 8-1 UFC) attempts to become the seventh when he challenges lightweight champ Eddie Alvarez (28-4 MMA, 3-1 UFC) for his 155-pound title in UFC 205’s pay-per-view headliner at Madison Square Garden in New York.

McGregor is 145-pound division’s current champ, he earned a welterweight win over Nate Diaz at UFC 202 in August, and now he attempts to put his name in the 155-pound win column while capturing the gold from Alvarez.

John Kavanagh, coach of the brash Irish fighter, called lightweight McGregor’s “Goldilocks weight,” meaning that while the cut to featherweight is a bit much – and the jump up to welterweight is a bit too much – fighting at lightweight is “just right” for him.

But how does McGregor compare physically while fighting in a 25-pound range over the past 11 months? Check out our image gallery to see photos from McGregor’s weigh-ins leading up to tonight’s historic UFC 205 headliner.

For more on UFC 205, check out the UFC Rumors section of the site.