McGregor made his MMA debut on March 8, 2008, beating Gary Morris by TKO.
Morris posted an 8-10 record as a fighter, with his last fight coming in 2016. It's unclear what he does today.
Two months later, McGregor took on Mo Taylor in his second fight. McGregor won by TKO, though it was close at one point, as Taylor got McGregor in a tough arm bar.
The McGregor fight was Taylor's debut, and it doesn't appear he fought again after.
On June 28, 2008, McGregor fought Artemji Sitenkov, a Lithuanian fighter.
Sitenkov beat McGregor by submission! He told reporters that he made 500 Euros off the fight and that McGregor was crying afterward. He went on to post a 15-16 career record. He has since opened two gyms and owns a pawnshop.
McGregor rebounded six months later with a win over Stephen Bailey by TKO.
Bailey only had one more professional fight after McGregor, but he fought one amateur fight in 2016. It's unclear what he does now.
After not fighting in 2009, McGregor returned to the octagon to fight Conor Dillion in October of 2010. McGregor beat Dillion by TKO in one of the longest fights of his career, clocking in at 4:22.
Dillon had a 5-8 record, with his last fight coming in 2016. He now owns the gym No Fear MMA in Ireland.
In November of 2010, McGregor took on Joseph Duffy, who took down McGregor by submission, handing "The Notorious" his second loss.
Duffy owns a 16-3 record and last fought in 2017. He is reportedly hoping to continue his career.
McGregor's first fight of 2011, a strong year for him, came against Hugh Brady. McGregor won by knockout.
Brady owns a 4-3 fighting record. He last fought in 2014.
On March 12, 2001, McGregor knocked out Mike Wood in 16 seconds.
Wood last fought in 2014 and said McGregor made him realize he wasn't cut out for UFC. Since, it appears he runs a YouTube channel and once auditioned for "The Voice."
One month later, McGregor took on Paddy Doherty. McGregor knocked him out in four seconds. Yes, four seconds.
Doherty last fought in 2013, finishing with a 4-9 record. He told Severe MMA in 2015 that he was no longer interested in fighting.
In June of 2011, McGregor took on Polish fighter Artur Sowinski, knocking him out in Round 2.
Sowinski owns an 18-10 record and is still fighting today. His most recent fight was a loss to Salahdine Parnasse in April.
About three months later, McGregor fought Aaron Jahnsen, knocking him out in the first round.
Jahnsen last fought in 2017 and owns a 5-6 record. Like McGregor, he gave a boxing a try, making his debut in the ring in February 2018.
In February of 2012, McGregor kept up his winning ways by beating Steve O'Keefe with another first-round knockout.
O'Keefe last fought in March of 2018 and owns a 9-3 record. In 2017, he founded Revolution Martial Arts, a gym in Greenhithe, England.
McGregor's next win came over Dave Hill in June 2012. It was a rare win by submission for McGregor.
McGregor's last fight of 2012 came against Ivan Buchinger. McGregor beat him by KO.
Buchinger is still fighting today. He owns a 34-6 record.
At last, in 2013, McGregor made his UFC debut against Marcus Brimage, knocking him out in the first round.
Brimage last fought in 2016 and was demoted from UFC. He owns a 7-7 record.
McGregor's second UFC fight was a win via unanimous decision over Max Holloway.
Holloway is 19-3 as of today and owns the 145-pound belt.
On July 19, 2014, McGregor fought Diego Brandao and beat him via TKO.
Brandao is still fighting. He owns a 23-13 record.
McGregor's next fight came against Dustin Poirier, who was beaten by knockout.
Poirier owns a 24-5 record. He is scheduled to fight Nate Diaz in November.
McGregor fought Dennis Siver on January 8, 2015 and knocked him out in the second round.
Siver owns a 23-11 career record. He left UFC in 2017.
Six months after fighting Siva, McGregor took on Chad Mendes and continued his winning ways, beating Mendes by knockout in the second round.
Mendes has an 18-4 career record. He returned from a two-year drug suspension in 2018 and beat Myles Jury in July.
In December of 2015, McGregor took on Jose Aldo. He beat Aldo by knockout in 13 seconds.
Aldo owns a 24-3 career record. He won his most recent fight, against Jeremy Stephens in July.
McGregor's next fights were even bigger. He fought Nate Diaz on March 5, 2016, then August 20, 2016. McGregor lost the first fight by submission, but won the second by majority decision.
Diaz owns a 20-11 record and is scheduled to fight Dustin Poirier in November. McGregor has said he wants a third and final fight with Diaz.
McGregor's last UFC fight came on November 12, 2016 against Eddie Alvarez. He won by TKO in Round 2.
Alvarez last fought in July, losing to Poirier. His UFC contract expired after. He has a record of 29-6.
In 2017, McGregor stepped outside of the octagon and into the ring to box Floyd Mayweather Jr. It didn't go so well for McGregor.
Mayweather, of course, is one of the greatest boxers ever and is 50-0. In September, he said he would be fighting Manny Pacquiao in a rematch, but it's unclear if the fight will actually happen.
And on Saturday, October 6, McGregor will take on Khabib Nurmagomedov in one of the biggest fights in UFC history. Who will take that one home?
Now, check out how McGregor spends all of the money he's made...
