Tennis Tracker: Sofia Kenin through in San Diego, Tiafoe loses in Davis Cup
23:59 CET - Another American triumph in San Diego with Danielle Collins (29) upsetting the odds to down second seed Caroline Garcia (29) in straight sets 6-2, 6-3 and advance on into the final four.
21:59 CET - It's all over between Sofia Kenin (24) and Anastasia Potapova (22), with the American coming out on top in San Diego 6-2, 6-3 in 78 minutes.
21:20 CET - We are underway over on the west coast in San Diego as home favourite Sofia Kenin (24) takes the first set in her quarter-final match against Anastasia Potapova (22) 6-2.
19:53: CET - Despite a second set comeback, Griekspoor (27) has completed the upset against American Tiafoe (25) after winning a deciding set tie-break. Big win for the Dutch! It finished 6-3 6-7 (7-9) 7-6 (7-3).
19:41 CET - And just now Jiri Lehecka (21) has given Czech Republic their second win of the day against South Korea, winning 6-1, 7-5 against Soonwoo Kwon (25).
19:34 CET - Elsewhere, Gabriel Diallo (21) gave Canada their second win of the day against Sweden as he defeated Elias Ymer (27) 6-4, 6-3.
19:32 CET - However, the favourite Tiafoe (25) bounces back for USA 7-6 (9-7) after vital tiebreak success.
18:22 CET - A slight shock could be on the cards as Tallon Griekspoor (27) has taken the first set against world number 11 Frances Tiafoe (25) 6-3.
18:07 CET - We have three more results to bring you from the Davis Cup. Firstly, Czech Republic's Tomas Machac (22) defeated Korea's Seong Chan Hong (26) in three sets 7-6 (10-8), 4-6, 6-2.
Canada go two wins from two in the early stages of this year's Davis Cup as Vasek Pospisil (33) was victorious against Sweden's Leo Borg (20) 7-6 (7-5), 5-7, 6-2.
Finally, world number 12 and Australia's top hope Alex De Minaur (24) made light work of Frenchman Ugo Humbert (25), winning 7-6 (7-2), 6-3.
16:55 CET - And the Dutchman takes the win against the American, ending the match in a 7-6, 6-2.
16:25 CET - Botic Van De Zandschulp (27) just won his first set against Tommy Paul (26) through a tiebreak 7-6.
15:52 CET - Adrian Mannarino (35) of France defeated Australian Max Purcell (25) 7-6, 6-4.
15:27 CET - Davis Cup is underway for the day, stay tuned as we bring you the latest here.
7:43 CET - Beatriz Haddad Maia needed three hours to get past Marta Kostyuk and reach the quarter-finals of the San Diego Open. Triumphing over the Ukrainian 7-5, 6-7, 6-2.
5:45 CET - Caroline Garcia managed to get past Sloane Stephens 6-3, 3-6, 6-1 to set up a quarter-final clash with Danielle Collins.
The American upset Jelena Ostapenko in the overnight action, winning 2-6, 6-3, 6-4.
Anastasia Potapova takes on Sofia Kenin for a place in the final four.