Kamaru Usman has been in more fights and has better experience than Khamzat Chimaev, but Khamzat Chimaev has youth on his side and the advantage of being better prepared than Kamaru Usman will be. Kamaru Usman will be brutal in the fight knowing that he has not fought since he lost to Leon Edwards, he will not want to loose this fight too even though he is being the replacement under a short notice and has a few days to  get to the required weight for the fight.