Belarusian Egor Gerasimov beat Andy Murray earlier in the week and now he is through to the Open Sud de France quarter-finals.
After surpassing the 1,000 mark for career wins, Rafael Nadal acknowledged he must be at his best to overcome Pablo Carreno Busta.
Adrian Mannarino had a host of opportunities to seize the advantage against John Millman but was ultimately soundly beaten.
Top seed Alexander Zverev has won 11 of his last 12 hard-court matches, but it was not all plain sailing against John Millman on Wednesday.
Health officials almost stopped Adrian Mannarino from facing Alexander Zverev at the US Open.
Fernando Verdasco fell to a third consecutive loss with an early exit at the Rio Open.
Rafael Nadal started his bid to seal the year-end number one status in Paris with a win over Adrian Mannarino.
Andrey Rublev's fine 2019 came to a disappointing end as Jo-Wilfried Tsonga ended his long wait for an ATP Masters 1000 match.
Happy Birthday to you, Andrey Rublev! The Russian had two reasons to celebrate following Sunday's Kremlin Cup final.
Former world number one Andy Murray was pushed all the way by Marius Copil before moving into the last four in Antwerp.