Fedora got a royal ass beaten on the ground by big foot, or was that religious fedor? He also got dominated by arona long before, and got robbed by rings judges (oh sorry the socoring in rings was different, he won by having a lame ankle lock attempt on arona ) if you consider fedor got his ass whoped more times by Bjj guys that not, that was his biggest problem dude had a good armbar from guard, who he always managed to pulled that vs guys with no so much Stellar ground games, he was a beast but his ground game was very rudimentary to say the best.
Maia also raped another undefeated sambo dude on his came back.
Sambo transitioning to mma solely inthink if you compare it to pure Bjj translate much better well combat sambo, thing Bjj is just a base and fighters now days all do Mma from young even if their base is Bjj, Bjj will always be the king on the mat that's just because people train more of the time mat work over other other disciplines that train more time in other areas.
I believe sambo dudes as most Russians are some of the toughest sob around, and kahbib, mother fucker was wrestling bears literally when he was 8, he ain't human.