20:05 CET - That will be all from our coverage of Monte Carlo today! Be sure to tune in for more action from the Principality tomorrow!
19:35 CET - In the final matches of the day, reigning and three-time Monte Carlo champion Stefanos Tsitsipas has survived a scare, fighting back from a set down to beat Jordan Thompson 4-6, 6-4, 6-2, while 14th seed Frances Tiafoe has battled to a 6-2, 5-7, 7-6 win over Miomir Kecmanovic.
19:23 CET - Jack Draper, one of the players of 2025 thus far, has started his campaign with a real statement of a win, with the fifth seed beating Marcos Giron 6-1, 6-1 in just an hour. The Brit is without a doubt one to watch this week.
18:03 CET - 20-year-old talent Arthur Fils was given a stern test by Tallon Griekspoor, but in the end, the Frenchman had enough to get over the line and seal a 6-7(3), 6-4, 6-2 victory.
17:16 CET - Matteo Berrettini has just clinched one of the biggest wins of his career, stunning world No. 2 and Monte Carlo top seed Alexander Zverev, 2-6, 6-3, 7-5! The big-hitting Italian played some fantastic tennis, and the highlight of the match came from a breathtaking 48-shot rally.
It is more heartbreak for Zverev though. The German has struggled for any sort of form since the Australian Open, and it is the second time this year he has failed to win a match at a Masters 1000 event.
16:55 CET - Tomac Machac has fought back to claim a fine win in Monte Carlo, defeating clay-court specialist Sebastian Baez, 3-6, 6-3, 6-2 in a little under two hours.
Meanwhile, Tomas Martin Etcheverry also progressed to the second round with a battling 4-6, 6-1, 6-4 victory over Corentin Moutet.
15:00 CET - Coming off the back of his title victory in Bucharest last week, Flavio Cobolli has followed that up with a 6-4, 6-2 win over Dusan Lajovic, moving into the second round in Monte Carlo.
14:45 CET - 36-year-old Roberto Bautista Agut put in a really accomplished performance to swat side Brandon Nakashima and move into the second round with a 6-2, 6-4 victory.
14:09 CET - Alexei Popyrin and Ugo Humbert have been involved in a thrilling, near three-hour clash, with the former eventually getting the better of his opponent - who looked to be struggling with a hand injury throughout - 2-6, 7-6(2), 6-4.
14:04 CET - Holger Rune has unfortunately had to retire ill from his opening round match with Nuno Borges. The Dane was trailing his Portuguese opponent, 6-2, 3-0, before withdrawing from the match. The 10th seed is out, while Borges will face Pedro Martinez in the second round.
13:36 CET - Pedro Martinez has advanced with a 6-4, 1-6, 6-2 victory over Lorenzo Sonego, who is enduring a poor run of form with one win in his last seven matches.
13:06 CET - Grigor Dimitrov is the first winner of the day at the Principality, claiming a 6-3, 6-4 win over Nicolas Jarry during a match which lasted an hour and 47 minutes. Dimitrov needed seven match points to finally seal the win and will face Monegasque player Valentin Vacherot next.
11:13 CET - Play is now underway in Monte Carlo, with Grigor Dimitrov, Ugo Humbert and Lorenzo Sonego all out on court.
08:45 CET - Hello and welcome to Flashscore's coverage of today's Monte Carlo action!
A clash between 15th seed Grigor Dimitrov and Nicolas Jarry at 11:00 CET will get the ball rolling, and that will be followed by a number of big games.
The standout match will see top seed Alexander Zverev face Matteo Berrettini, while reigning champion and Monte Carlo specialist Stefanos Tsitsipas will take on Jordan Thompson.