World No 1 Daniil Medvedev defeated Ilya Ivashka for the second time in six days to reach the Halle grass court quarterfinals on Thursday.
Medvedev triumphed 7-6 (7/4), 6-3 over the 42nd-ranked Ivashka having also got the better of the Belarusian in the quarterfinals at 's-Hertogenbosch last week.
Top seed Medvedev fought off three set points at 4-5 in the opening set before going on to clinch it in a tie-break.
The second set was far more straightforward with the 26-year-old Russian wrapping up victory in one hour and 36 minutes.
"He is a great player," said Medvedev. "He had a lot of bad luck with injuries at the beginning of the season. At the end of last season he was playing really great tennis.
"I've known him since I was very young, we actually played each other in Futures, Challengers, and on the ATP Tour. He beat me once in Davis Cup, which is a really important tournament.
"He knows how to play well on grass, so I'm really happy that two times in a row I managed to pass a tough test."
Medvedev next faces seventh seed Roberto Bautista Agut for a place in the semifinals.
Halle is a warm-up event for Wimbledon but Medvedev and his fellow Russian and Belarusian players won't be there after being banned following the invasion of Ukraine.