Really hard to say, especially as I've hardly played anything against humans.
But here are some candidates:
Hang-On, Slap Shot or Tennis Ace (Sega Master System)
Crush! Deluxe (strategy game)
Wing Commander Academy
Fatal Racing (aka Whiplash in NA)
So, I was just checking that wiki page for Fatal Racing because I thought it had an alternative title I didn't remember.
And, having played the games tens of times along 25 years... I'd never realized all the opponents are named after scifi robots or computers! About a third I didn't know, another third wouldn't have remembered and most of them are common names (or something like Nomad is just typical cool game character name), so I'd never really thought of them.
Took me 25 years to find this out