Looking at the UFC's champions at the beginning and end of the decade (2010-2019)

Lightweight: BJ Penn and Khabib Nurmagomedov

Khabib Nurmagomedov currently holds the UFC Lightweight title

BJ Penn went into 2010 with a reputation as perhaps the greatest Lightweight fighter ever seen in the sport, but his UFC title reign was surprisingly cut short just 4 months into the decade, as Frankie Edgar defeated him in a controversial decision. Edgar proved the win wasn’t a fluke by defeating Penn in a rematch, but just under two years later, he dropped the title to Benson Henderson.

Henderson managed 3 defenses before losing to Anthony Pettis, and from there the title was passed around like a hot potato, from Pettis to Rafael Dos Anjos, to Eddie Alvarez and to Conor McGregor. McGregor’s reign ended with him relinquishing the belt with no title defences, and some normality was finally restored to the division in 2018 when Khabib Nurmagomedov claimed the vacant title by defeating Al Iaquinta.

Nurmagomedov has since made 2 successful defences – over McGregor and Dustin Poirier – and going into the next decade, he holds a reputation similar to that of Penn going into 2010, as potentially the greatest 155lber ever seen in the sport. He will next defend against Tony Ferguson in early 2020.