BoxRec

Prime vs prime, who wins?

Mercer Late round TKO.

Mercer by DQ, surely.

If Golota fought him the way he did Witherspoon, he'd win a clear UD, but he wouldn't.

Golota at his best physical and mental state could outbox Mercer. In any case, Mercer would have real chances of pulling out a stoppage win.

Mercer stops him around the 9th round.

As always with Golota, you never know what you are going to get. It could have been a very good fight. There really wasn't much difference in ability. The Mercer who should have the decision against Lewis and gave Holyfield a tough fight would have won easily. Same if Golota just mailed it in.
But if Mercer fought listless fight like against Ferguson, and Golota came to fight, could actually pull it off. though he probably would get dq'd or quit while ahead.

In a nutshell, hard to predict how Mercer would win, but he almost for sure would have.

Mercer would wear Golota down with jabs and body shots to either take a decision or late round stoppage.

Mercer finds a way to win, Golota a way to lose.