does Umar lack heart or was it lack of experience?

[KhabibPink]

Relatively speaking, of course. Islam proved that he can keep moving forward in the first Volk and the Dustin fight even if he is tired but Umar was visibly exhausted, couldn't maintain a good poker face and he looked defeated, especially in the championship rounds. He beat Cory in a five round fight but he was mostly dictating the whole thing and was never pressured like he was this time.
Or was it just a lack of experience, against the worst fucking guy possible in Merab?
I like Umar tho. I can see him becoming champion as he is young but curious to see, now that he lost his 0, whether he will get better like Islam did or will this sorta damage him moving forward.

He lacks neither, he just went up against an Alien in Merab, he looked good aswell.