08:43 CET - Over in Bogota, top seed Marie Bouzkova (25) and home favourite Camila Osorio (22) have sealed their spots in the semi-finals after three-set wins over Laura Siegemund (36) and Tatjana Maria (36) respectively.
07:53 CET - Frances Tiafoe (26) battled through a tight first set to overcome Jordan Thompson (29) 7-6(8), 6-4 in Houston. The third-seeded American will face Luciano Darderi (22) in the semi-finals after the Italian shocked Marcos Giron (30) 6-0, 6-4.
07:40 CET - Good morning! Third seed Maria Sakkari (28) continued her impressive recent form with a comfortable 6-2, 6-4 victory over Veronika Kudermetova (26) to seal a spot in the Charleston semi-finals.
The Greek will face Miami Open champion Danielle Collins (30) in the last four after the American earned a routine 6-3, 6-4 win against Elise Mertens (28).
00:05 CET - Over in Houston, Ben Shelton (21) downed Brandon Nakashima (22) 7-5, 7-6 to move into the semi-finals.
While in Bogota, Sara Errani (36) beat Irina Bara (29) 4-6, 6-2, 6-3 to move into the final four.
Tune into the Tennis Tracker tomorrow morning for a full roundup of the rest of the overnight action in Colombia and the USA!
22:50 CET - Top seed Jessica Pegula (30) is through to the final four in Charleston after beating 12th seed Victoria Azarenka (34) 6-4, 3-6, 7-6(7).
21:30 CET - Top seed Casper Ruud (25) has cruised past Marton Fucsovics (32) 6-3, 6-2 and into the final four in Estoril. Next up for Ruud is Spaniard Pedro Martinez (26).
21:00 CET - Mariano Navone (23) has wrapped up the final semi-final berth in Marrakech after beating Aleksandar Vukic (27) 6-2, 6-4. The Argentine will face Matteo Berrettini (27) next.
20:12 CET - In around five minutes time number one seed Casper Ruud (25) is to be in action in Portugal against Hungarian Marton Fucsovics (32).
20:08 CET - Meanwhile a retirement from American Michael Mmoh (26) in Morocco has given Argentine Tomas Martin Etcheverry (30) a semi-final spot. Etcheverry had taken the first set 6-3 before Mmoh's retirement early on in the second set.
20:05 CET - Back to Portugal and Pedro Martinez (26) has made no mistake in dispatching veteran player Richard Gasquet (37) to progress to the semi-finals, winning 6-4, 6-4.
19:52 CET - Daria Kasatkina (26) has avoided a potential upset by defeating Jaqueline Cristian (25) 6-7 (4-7), 6-2, 6-3 to make the semi-finals in Charleston. Up next in Charleston is number one seed Jessica Pegula (30) against Victoria Azarenka (34).
19:30 CET - Matteo Berrettini's (27) continued return to something close to his best form continued in Marrakech this evening as he progressed to the semi-finals with a victory over fellow Italian Lorenzo Sonego (28), winning 6-3, 7-6 (7-5).
18:30 CET - Nuno Borges (27) has been knocked out of his home tournament after a 6-2, 7-6 (7-3) loss to Chile's Cristian Garin (27).
17:10 CET - Fabio Fognini (36) has been knocked out of the Marrakech Open after losing 6-1, 6-2 against Pavel Kotov (25) to progress with ease in Morocco.
16:10 CET - A first result of the day to bring you from Marrakech, with Spain's Roberto Carballes Baena (31) battling past Nicolas Moreno De Alboran (26) 6-4, 4-6, 6-4.
15:27 CET - After an underwhelming early exit in Miami, Hubert Hurkacz (27) has continued to bounce back strongly this week in Portugal. He booked his place in the semi-final this afternoon with a 7-6 (7-4), 6-4 victory over Pablo Llamas Ruiz (21).
12:00 CET - Hello and welcome to today's Tennis Tracker on what promises to be an exciting day of action.
Several of the world's top players are in action later, including Jessica Pegula (30), Casper Ruud (25) and Danielle Collins (30).
However, before all of that, the first match of the day sees Hubert Hurkacz (27) take on Pablo Llamas Ruiz (21) for a spot in the semi-finals at the Estoril Open.
