Ryan Peniston beat another notable name on British grass by fighting back to overcome French Open quarter-finalist Holger Rune at Eastbourne.
The British men's number six beat world number five Casper Ruud on his way to the Queen's quarter-finals last week.
In the final event before Wimbledon, Peniston, 26, won 4-6 7-6 (7-5) 6-1 against Denmark's eighth seed Rune.
Meanwhile, Katie Boulter came back to beat 2021 Wimbledon runner-up Karolina Pliskova in the WTA second round.
Boulter, the British women's number four, responded impressively after the Czech dominated the opening set to prevail 1-6 6-4 6-4 and secure her first win over a top-10 opponent.
The 25-year-old twice broke Pliskova's serve for 2-0 and 4-2 leads in the deciding set, eventually sealing victory on the world number seven's serve in the 10th game.
"I'm super proud of myself today," said Boulter, who will play Czech two-time Wimbledon champion Petra Kvitova or Croat Donna Vekic next.
"I worked so hard today to battle and fight. Against a player like that, it means so much to come through."
Peniston will play a Spanish opponent in the second round, either Alejandro Davidovich Fokina or Pedro Martinez.
Rune, aiming for his first tour-level win on grass to reach the second round, was twice two points away from victory - at 6-5 in the second set and 5-5 in the tie-break.
After being broken early in the third set, the 19-year-old drew jeers from the Eastbourne crowd for hitting a ball out of court and kicking his towel bin.
"I'm very happy with that. A tough start but I managed to fight thanks to you guys," Peniston told the home crowd.
"Since Queen's it has been madness. A couple of weeks ago was a lot different and things have changed. But I'm loving it."
Three other Britons are playing in the singles later on Tuesday at the Rothesay International, but the headline act is the return of Serena Williams to the court after a year out.
Williams, 40, has not played since she was injured at Wimbledon last year and is competing in the women's doubles alongside Tunisia's Ons Jabeur.
Williams and Jabeur, who is third in the WTA singles rankings, will take on Spain's Sara Sorribes Tormo and Marie Bouzkova of the Czech Republic on Eastbourne's centre court at about 18:30 BST.
That match is preceded by British men's number two Dan Evans' first-round match against France's Adrian Mannarino.
Jodie Burrage meets Spanish top seed Paula Badosa on court one as she looks to eclipse her comeback win over Croatia's world number 80 Petra Martic on Monday - which was the biggest victory of her career by ranking.
Harriet Dart, the second highest-ranked British woman behind the absent Emma Raducanu, takes on Swiss player Jil Teichmann on court two.