LAS VEGAS – Khabib Nurmagomedov (27-0 MMA, 11-0 UFC) is still perfect, after tapping out Conor McGregor (21-4 MMA, 9-2 UFC) in the fourth round via rear-naked choke.

The lightweight title bout was the main event of today’s UFC 229 show at T-Mobile Arena in Las Vegas. It aired on pay-per-view following prelims on FS1 and UFC Fight Pass.

McGregor walked forward with his hands low to start the fight, stalking from the center. A McGregor high kick was blocked, and Nurmagomedov responded but shooting from distance. McGregor was quick to react, sprawling and nearly sneaking around to the back. However, Nurmagomedov refused to let go of a single leg and eventually was able to bring the action to the canvas. McGregor remained calm underneath, looking almost bored as Nurmagomedov triangled his legs and kept his opponent pinned to the canvas. McGregor was busy from his back, sneaking in a few elbows and punches, and Nurmagomedov kept control of the positioning and brought in a few punches of his own.

McGregor remained seated, with his back against the fence, and the crowd loudly booed and asked for referee Herb Dean to intervene. He declined, and Nurmagomedov retained complete control, eventually dragging McGregor to his back. Working from half-guard, McGregor tried to hold tight, but Nurmagomedov did find room to strike a bit before the bell.

McGregor again kept his hands low to start the second, immediately flashing out a few kicks to the body. A Superman punch and leaping knee missed, and Nurmagomedov rocked his foe with a huge right hand. With McGregor wobbled, Nurmagomedov rushed forward with a flying knee and nearly walked into a devastating blow, but he recovered, slowed, and picked McGregor up and tossed him to the canvas in emphatic fashion.

McGregor recovered well underneath and tried to slow things down, but Nurmagomedov worked ground-and-pound attacks from inside his opponent’s guard. Nurmagomedov eventually postured, rising to his feet and punching away as McGregor covered on the floor. is head near the cage, McGregor didn’t have much room to move, and Nurmagomedov capitalized. After a few big shots, Nurmagomedov passed down to side control, where McGregor seemed to tag him with an illegal knee, though the fight carried on. Nurmagomedov teased a potential kimura, though McGregor worked his arm free and got to a seated position. Nurmagomedov tried to grab the neck, but McGregor rose to his feet, bringing the crow to a fever pitch. However, Nurmagomedov stayed tight to the body, and the round ended in the clinch.

McGregor looked to tee up the big left in the third, and he did find a home for it in the early going. Nurmagomedov seemed bothered but didn’t fall. McGregor controlled the center, and Nurmagomedov moved laterally on the outside, taking a few punches along the way. McGregor kicked the legs a bit andmissed a combination but was able to get inside on the legs. McGregor defended the first effort, but Nurmagomedov pushed forward again and moved into the clinch, pushing his opponen t ot he fence. McGregor was able to puhs him away, and he again landed the left hand when they returned to the center.

Nurmagomedov seemed content to play a dangerous game, trading punches in the pocket with the vaunted knockout artist. It was clear McGregor was tiring, but he also was still throwing with power. Nurmagomedov eventually pushed inside and again wrapped the body, though McGregor sprawled well against the fence. Nurmagomedov was happy to stay tight to the body, though he couldn’t get the fight to the floor before the end of the frame. Dean warned McGregor of an illegal elbow to the back of the head in the final exchange, but no points were taken.

McGregor was out quickly in the fourth. A straight left did land, but Nurmagomedov answered with a left hook of his own. McGregor was clearly tired, but he kept looking for the big shot. Nurmagomedov stayed true to his approach, shooting forward and dragging McGregor to the canvas. To his credit, McGregor worked quickly to his feet, but Nurmagomedov stayed tied to his back and drug him back tot he floor, even with McGregor trying to grab the cage to prevent the advance.

Nurmagomedov set firm in top position, briefly teasing an arm-triangle choke but letting it go in favor of keeping position. The decision paid off, and when his opponent turned to try and rise, Nurmagomedov was there to wrap the neck, squeezing with the rear-naked choke until McGregor was forced to tap at the 3:03 mark of the fourth round.

The fantastic performance was quickly marred, however, by an all-out brawl between the two teams that took place both in and out of the cage, ignited by Nurmagomedov leaping the cage to go after McGregor’s cornermen.

Up-to-the-minute UFC 229 results include:

Khabib Nurmagomedov def. Conor McGregor via submission (rear-naked choke) – Round 4, 3:03 Tony Ferguson def. Anthony Pettis via TKO (corner stoppage) – Round 2, 5:00 Dominick Reyes def. Ovince Saint Preux via unanimous decision (30-27, 30-27, 30-27) Derrick Lewis def. Alexander Volkov via knockout (punches) – Round 3, 4:49 Michelle Waterson def. Felice Herrig via unanimous decision (30-26, 29-28, 30-27) Jussier Formiga def. Sergio Pettis via unanimous decision (30-26, 29-28, 29-28) Vicente Luque def. Jalin Turner via knockout (punches) – Round 1, 3:52 Aspen Ladd def. Tonya Evinger via TKO (strikes) – Round 1, 3:26 Scott Holtzman def. Alan Patrick via knockout (elbows) – Round 3, 3:42 Yana Kunitskaya def. Lina Lansberg via unanimous decision (30-27, 30-27, 30-27) Nik Lentz def. Gray Maynard via TKO (kick, punches) – Round 2, 1:19 Tony Martin def. Ryan LaFlare via TKO (kick, punches) – Round 3, 1:00

For complete coverage of UFC 229, check out the UFC Events section of the site.