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.
Daniil Medvedev decided not to chase a seventh straight final due to fatigue but Karen Khachanov thrilled fans at the Kremlin Cup in Moscow.
Lorenzo Sonego was no match for Jo-Wilfried Tsonga in Antwerp, while Janko Tipsarevic made an announcement over his future in Stockholm.
World number one Novak Djokovic will face Lucas Pouille in the last eight in Tokyo after getting past Go Soeda.
Adrian Mannarino was no match for Alex de Minaur, who continued an impressive season with victory at the Zhuhai Championships.