Ivan Lendl defeated Andrei Cherkasov 6-3 6-2 6-3 in the Australian Open quarter-final on hard.
Lendl I. took it in straight sets.
Ivan Lendl beat Andrei Cherkasov 6-3 6-2 6-3. Umpiry, "Ivan Lendl vs Andrei Cherkasov — Australian Open Quarter-final", https://umpiry.com/match/1990-01-15/cherkasov-vs-lendl-australian-open-qf?utm_source=cite (as of 15 January 1990).