Khabib Nurmagomedov beat Conor McGregor to take his MMA record to 27-0 and hold on to the UFC lightweight title at UFC 229.
McGregor started quickly getting two shots off early but Khabib went with the expected plan by soon going for the legs and taking it to the ground.
The Notorious did well with his defence and didn't take much damage, managing to get some shots away as the Russian squeezed him on the ground for most of the 1st.
A big right from Khabib at the start of the second was followed by a knee from McGregor and once again the Russian took the challenger to the ground.
This time though 'The Eagle' managed to land some big right hands and a big left elbow to the side of McGregor's head.
After a flurry of shots from the champ and more holding, McGregor was able to get to his feet and take it to the third round.
The crowd were clearly with McGregor and gave him a big roar as he stepped up from his seat at the beginning of the third and caught his opponent with some big shots early in the round.
The pair exchanged shots but the former champion was the one landing the bigger ones as Khabib failed to keep him back on the mat.
The fourth started as a tetchy affair, McGregor landing a couple of shots, before Khabib tripped the one time boxer and again took him to the mat.
This time the reverse choke led McGregor to tap out.
Conor McGregor and Khabib Nurmagomedov fought in Las Vegas' Staples Centre at UFC 229 with the UFC lightweight title on the line in the company's biggest ever fight.
It had been two years since Conor McGregor stepped foot inside and octagon on a big UFC night, having taken a year out to have a boxing fight with Floyd Mayweather, and his return was in the biggest fight of his career.
The Notorious returned to face unbeaten Russian Khabib Nurmagomedov who had won the lightweight title that McGregor previously held, and never lost in a fight, earlier in the year and defended the title against the Irishman.
The pair's rivalry had become heated in the build up to Khabib's title fight with Al Iaquinta after McGregor attacked the bus the Russian was on, following a clash between him and McGregor's friend Artem Lobov.
During the pre fight press conferences the former lightweight and featherweight champion had targeted his unbeaten counterpart for his politics and gone really personal with Khabib's manager too.
In the octagon, before the bell rang, the pair refused to touch gloves after all animosity leading up to the fight.