22:08 CET - A relative upset has rounded off the play in Stuttgart with Linda Noskova (19) knocking out eighth seed Jelena Ostapenko (26) with ease in 67 minutes. The Czech world number 31 won the tie 6-3, 6-1 to advance.
Elsewhere, no such upset in Rouen, where top seed Anastasia Pavlyuchenkova (32) has beaten France's Alice Robbe (23) 6-2, 6-2.
21:11 CET - Despite winning the second set in a tie-break, Harold Mayot (22) has been forced to retire in his round-of-32 clash with 12th seed Cameron Norrie (28). The pair were locked after two tie-breaks, but it is Norrie who advances.
21:00 CET - Over to Rouen and second seed Caroline Garcia (30) is through to the next round thanks to a hard-fought 6-1, 3-6, 7-5 win over Italy's Elisabetta Cocciaretto (23).
20:38 CET - The penultimate game of the day in Barcelona has come to a close with 13th seed Tomas Martin Etcheverry (24) has seen off the challenge of Nick Hardt (23) in straight sets 7-5, 6-2 in 105 minutes. In Stuttgart, Elise Mertens (28) is through after a see-saw battle with Tatjana Maria (36). The Belgian was victorious 6-1, 4-6, 6-0.
19:53 CET - Miomir Kecmanovic (24) has seen off the challenge of David Goffin (33) in Bucharest, triumphing 6-4, 3-6, 6-3. Elsewhere, Clara Burel (23) and Yue Yuan (25) are both through to the last-16 in Rouen.
18:47 CET - Over in Stuttgart, Marketa Vondrousova (24) has sealed her spot in the next round after a routine 6-4, 6-3 win over Donna Vekic (27).
18:38 CET - The King of Clay is back. Rafael Nadal (37) has marked his first match on the ATP Tour since January with a convincing 6-2, 6-3 victory over Flavio Cobolli (21). Next up for the 12-time Barcelona champion is a tricky test against fourth seed Alex de Minaur (25) tomorrow.
16:50 CET - Rafael Nadal (37) is back on court! His opening round clash against Flavio Cobolli (21) will be getting underway in the next couple of minutes.
16:43 CET - There's been a big shock in Barcelona, with second seed Andrey Rublev (26) losing in straight sets 6-4, 7-6(6) to American Brandon Nakashima (22). That's a fourth consecutive defeat for the Russian and he didn't take it well.
16:35 CET - Felix Auger-Aliassime (23) battled back from a set down to outlast Maximilian Marterer (28) 6-7(5), 7-6(6), 7-6(3) in a marathon three-and-a-half-hour contest in Munich.
15:14 CET - Following her pair of victories at the Davis Cup last week, Qinwen Zheng (21) followed those up with a convincing win in Stuttgart, easing past Sorana Cirstea (24) 6-2, 6-3.
14:43 CET - Cristian Garin (27) and Taro Daniel (31) are both through in Munich after straight-set wins over Dominik Koepfer (29) and Christopher O'Connell (29) respectively.
14:12 CET - Denis Shapovalov's (25) woes continue after a 6-4, 6-2 defeat to Corentin Moutet (24) in Bucharest, while Borna Coric (27) has been knocked out in Barcelona by Facundo Diaz Acosta (23).
14:05 CET - World number 14 Jasmine Paolini (28) is safely through in Stuttgart after an emphatic 6-1, 6-0 victory over fellow Italian Sara Errani (36).
12:20 CET - A couple of early results to bring you, with Dusan Lajovic (33) easing past Diego Schwartzman (31) 6-1, 6-2 in Barcelona and wildcard Joao Fonseca (17) shocking Lorenzo Sonego (28) 7-6(5), 7-5 in Bucharest.
10:40 CET - We've got a busy day ahead with plenty of enthralling tennis across Europe. The headline match comes in Barcelona where Rafael Nadal (37) returns to competitive action against Flavio Cobolli (21). That clash is due to get underway around 16:00 CET.
Other big names in action today include Andrey Rublev (26), Qinwen Zheng (21), Jelena Ostapenko (26) and Stan Wawrinka (39).
10:15 CET - Good morning and welcome to today's Tennis Tracker!
