Tennis Tracker: Nadal wins four-hour thriller against Navone, Zverev and Zheng through
23:19 CET - Qinwen Zheng (21) was in utterly formidable form in Palermo, crushing Jaqueline Cristian (26) ruthlessly, 6-1, 6-1.
22:53 CET - Marcos Giron (30) had little issue cruising into the final four of Newport, coasting past Alex Bolt (31) 6-4, 6-1.
22:04 CET - Portugal's Nuno Borges (27) has moved into the Bastad semis, beating Timofey Skatov (23) 6-4, 6-3.
21:15 CET - Christopher Eubanks (28), Thiago Agustin Tirante (23) and Eva Lys (22) have all claimed wins at their respective tournaments to move into the final four.
20:05 CET - French Open finalist and defending champion Alexander Zverev (27) is through in Hamburg, ousting Zhizhen Zhang (27) 6-4, 6-3 on the German clay.
19:52 CET - Sixth seed Matteo Berrettini (28) is through to the semi-finals in Gstaad, edging past Canada's Felix Auger-Aliassime (23) 7-6(7), 7-6(2) in two competitive sets.
18:34 CET - Diana Shnaider's (20) good recent form continued with a straightforward 6-4, 6-2 victory over Ella Seidel (19) in Budapest.
Meanwhile in Hamburg, Pedro Martinez (27) secured an impressive win, defeating Francisco Cerundolo (25) 1-6, 6-1, 6-4.
17:44 CET - What a match. Rafael Nadal (38) has just demonstrated all the fighting qualities he's shown time and time again throughout his career, recovering from a set down to outlast fourth seed Mariano Navone (23) 6-7(2), 7-5, 7-5 in a four-hour slugfest in Bastad.
16:25 CET - Top seed Stefanos Tsitsipas (25) is safely through to the last four in Gstaad, securing a relatively routine 6-4, 6-3 victory over Italian veteran Fabio Fognini (37).
16:12 CET - The next player through to the Hamburg semi-finals is Arthur Fils (20), after his opponent Holger Rune (21) was forced to retire when trailing 4-6, 1-4.
14:42 CET - Fifth seed Jan-Lennard Struff (34) has booked his spot in the Gstaad semi-finals, battling past Tomas Martin Etcheverry (25) 7-5, 3-6, 6-3.
Meanwhile, in Hamburg, Sebastian Baez (23) recovered from a set down to overcome Italy's Luciano Darderi (22) 2-6, 6-4, 6-4 in just over two hours.
12:47 CET - Aliaksandra Sasnovich (30) is through to the last four in Budapest after a hard-fought 6-4, 2-6, 6-4 victory over Suzan Lamens (25).
12:24 CET - Quentin Halys (27) is the first winner of the day in Gstaad, with the Frenchman beating Gustavo Heide (22) 6-1, 7-5 to progress to the semi-finals.
11:08 CET - Before we look ahead to play today, there's a result to bring you from late last night, with Reilly Opelka (26) continuing his impressive comeback, beating Mackenzie McDonald (29) 4-6, 6-3, 6-4 in the Newport quarter-finals.
10:30 CET - Good morning and welcome to our coverage of today's tennis action!