Arnold Allen decisions Melquizael Costa in UFC Vegas 17 main event

The octagon returned to Sin City for Saturday's UFC Vegas 117: Allen vs. Costa event at the Meta Apex.

The fight card was headlined by a featherweight bout between No. 7 ranked Arnold Allen and No. 12 ranked Melquizael Costa. Allen entered the bout having lost three of his last four fights and in need of a win to maintain relevance in the top of the division. Costa brought with him a six-fight winning streak.

Allen landed firasr worth a leg kick and pressed forward. Costa landed a leg kick in return. Allen continued to walk forward. He landed a righ hand that knocked Costa down. Allen gained top position and worked to keep Costa grounded. Costa worked his way up and gained top control. He was able to take Allen's back. Allen stood but Costa stayed on him and drug him back down. Allen stood and Costa took his back. Costa looked to sink in a choke. Allen defended, gained top position and delivered elbows. MMAWeekly scored the round 10-9 for Allen.

Allen pressured Costa to start the second. They exchanged leg kicks. Allen connected with a right hand and Costa fired back with a combination. Allen stopped in the pocket with a 1-2. Costa circled on the outside and utilized let kicks. Costa pressed forward with punches but slipped while throwing a high kick. Allen stood over him kicking his legs. He let Costa up. Costa began going to the body with his kicks. MMAWeekly scored the round 10-9 for Allen, but it was a competitive round.

Allen against pressed forward in the third. He landed his jab but Costa responded with a combination. They exchanged leg kicks and Costa delivered a kick to the body. Costa had a higher output in the first half of the frame. Allen connected with a combination. He followed up with a clean left hand. Costa looked to get the fight to the ground but ended up having to pull guard. Allen landed an elbow and Costa rolled to his knees. Allen peppered him with right hands. Allen let him up in the closing seconds. MMAWeekly scored the round 10-9 for Allen.

Costa came out in the fourth with a heavy kicking attack. He connected with a combination. Allen responded with a right hand. Costa connected with a right of his own. Allen's jab landed. Costa stepped in the pocket with a 1-2. Allen reacted with a left hand and clinched. He tripped Costa to the canvas just over the midway mark in the round. He maintained top position before letting Costa up. Allen's left hand found a home. MMAWeekly scored the round 10-9 for Allen.

Allen pressed forward but ate a counter left hand. Costa pressured Allen with punches. They clinched and Allen tripped Costa to the canvas. Costa worked his way upright but didn't escape the grasp of Allen. Allen pulled Costa back to the ground. Costa again got to his feet only to be put on his back again. Costa stood but Allen took his back. Costa flopped to his back trying to get free but Allen stayed on his back. Allen delivered left hands. MMAWeekly scored the round 10-9 for Allen.

The judges saw Allen as the unanimous winner. The scorecards read 50-45, 50-45, and 49-46.

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This story was originally published May 16, 2026 at 11:12 PM.