Andy Murray beat Philipp Kohlschreiber for the second time in three days to advance to the third round of the Madrid Open in a match that finished just before 3am local time.
The delayed match, which began at 1am, looked like it would be over quickly when Murray made a quick start but Kohlschreiber dug in to take it to three sets before tiredness took hold of the German.
Second seed Murray's 6-4 3-6 6-0 triumph came hot on the heels after he secured his first-ever clay title at Kohlschreiber's expense in Munich on Monday, but this was a clash that was made even harder by the fact it dragged out into the early hours of Thursday morning.
Top-seeded Roger Federer made an early exit in a thrilling second-round loss to Nick Kyrgios.
The 20-year-old Australian ended Federer's hopes of a fourth title at the Spanish tournament by rallying for a 6-7(2) 7-6(5) 7-6(12) victory.
Kyrgios is in form, having reached the final at the Portugal Open before losing to Richard Gasquet. The 2014 Wimbledon quarter-finalist also relinquished his status as the ATP's highest-ranked teenager by turning 20 last week.
Federer said his problem was that "I couldn't return his first serve. It was just a horrible performance on the return."
Kyrgios said he had been excited at the prospect of playing his childhood hero.
"Last night it was a bit tough to get some sleep," he said. "I've been playing well recently on the clay, so I knew I had a good chance to go out there and do well. I stuck to my game and served well and I got the win."
Clay king Rafael Nadal broke Steve Johnson's serve three times in a 6-4 6-3 win and is aiming to extend his streak of winning at least one European ATP World Tour clay court title in the run-up to Roland Garros to 11 consecutive years.
In other men's results, sixth-seeded Tomas Berdych beat Richard Gasquet 7-6(3) 7-5 and No.7 David Ferrer had a 6-4 6-0 win over fellow Spaniard Albert Ramos-Vinolas.
The 10th-seeded Grigor Dimitrov rallied for a 3-6 6-2 7-5 victory over Fabio Fognini, John Isner beat Thomaz Bellucci 7-6(5) 6-7(11) 6-1, Simone Bolelli had a 4-6 6-3 6-2 win over Luca Vanni in an all-Italian matchup, and Jo-Wilfried Tsonga ousted Jack Sock 6-3 1-6 7-6(4).