French duo Lucas Pouille and Julien Benneteau reached the quarter-finals of the Open 13 Provence in Marseille.
Third seed Pouille, the runner-up to countryman Jo-Wilfried Tsonga 12 months ago, survived a testing encounter with another French player, Pierre-Hugues Herbert, winning 3-6 7-6 (8/6) 6-4.
Benneteau, playing in his final season, had another moment to savour in front of his home fans as he defeated fifth seed Roberto Bautista Agut 7-6 (7/2) 7-6 (7/5).
There was another miraculous comeback from seventh seed Damir Dzumhur, who eventually defeated Italy's Thomas Fabbiano 6-7 (5/7) 7-6 (9/7) 7-6 (7/5).
Dzumhur saved four match points in his first-round win over Mikhail Kukushkin and on Wednesday recovered from 0-5 in the third-set tie-break, winning the final seven points.
Nicolas Mahut made it three French winners in a day with a 7-5 7-6 (7/4) victory over young Greek Stefanis Tsitsipas in the first round while there were also wins for Gilles Muller and Mischa Zverev.
Jack Sock, John Isner and Milos Raonic were dumped out of the Delray Beach Open, while Marin Cilic's Rio Open clash with Gael Monfils was left on a knife edge when rain halted play.
In a stunning upset top seed Sock was defeated by wildcard fellow American Reilly Opelka, a 6ft 11in 20-year-old who is 200 places below him in the ATP rankings.
Opelka hit 17 aces and fought back from defeat in the first set to finish off the defending champion 4-6 7-5 6-3 and secure a quarter-final showdown with Peter Gojowczyk.
In his own upset, the German defeated number six seed Isner 7-6 (7/3) 6-7 (4/7) 7-6 (7/5) despite the American firing off 30 aces during the two-and-a half-hour match.
Canadian former world number three Raonic, who won for the first time in 2018 in round one, was eliminated by American Steve Johnson 6-2 6-4.
The ninth seed, Raonic struggled with injury during 2017 and has only won two tour-level matches in six months.
Johnson progresses to meet Russia's Evgeny Donskoy, who saw off American Donald Young 7-6 (8/6) 6-3.
In Rio, rain on the clay court forced the suspension of Cilic and Monfils' second round match with the second set tie-break level at 7-7.
The Frenchman was leading Cilic, the top-seeded player in the tournament, 6-3 6-6.
In other matches number four seed Albert Ramos-Vinolas was beaten by Nicolas Jarry 7-5 6-3, while number six seed Diego Schwartzman won his second-round match against fellow Argentinian Federico Delbonis 6-2 6-3.