Stefanos Tsitsipas fought back impressively to progress at the Rotterdam Open, but fellow seed Fabio Fognini tumbled out of the tournament on Tuesday.
Tsitsipas lost the opening set to Hubert Hurkacz and also slipped 2-0 behind in the second, yet he dropped only two further games as he progressed 6-7 (2-7) 6-3 6-1.
The world number six, who had failed to register a victory in his previous appearances at the tournament, moves on to face Aljaz Bedene, a 6-2 6-4 winner against Benoit Paire.
Andrey Rublev, the seventh seed aiming to win a third title already in 2020, wasted little time in reaching the last 16, dismissing Nikoloz Basilashvili 6-2 6-3 in under an hour.
Next up for Rublev will be Alexander Bublik, who came through a tense three-set battle against French qualifier Gregoire Barrere.
Fognini, meanwhile, lost in straight sets to Karen Khachanov, the Russian converting four of the seven break-point opportunities that came his way against the fifth-seeded Italian.
Felix Auger-Aliassime lost five straight games in the second set against Jan-Lennard Struff but eventually prevailed in a decider, his 6-3 1-6 6-3 victory booking a clash with 2018 runner-up Grigor Dimitrov.
In the final match of the day, Filip Krajinovic defeated home wildcard Tallon Griekspoor 6-4 6-1.