Cameron Norrie's poor form continued as he crashed out of the Rothesay International in Eastbourne following a disappointing first-round defeat by world No88 Emil Ruusuvuori.
The former British No1 has slipped outside the top 40 after losing nine of his previous 15 matches, including first-round exits at the French Open and Queen's.
Norrie, who was also beaten by world No773 Jack Pinnington Jones at Nottingham, saw his miserable run extended by a 7-6 (9) 6-3 exit at the hands of 25-year-old Finn Ruusuvuori.
The 28-year-old was ranked eighth in the world just 18 months ago and will begin Wimbledon next week with only limited competitive preparation on grass.
Norrie failed to capitalise on two break points in the sixth game of a tight opening set and was subsequently unable to seize a pair of set points in the tie break.
Ruusuvuori recovered from both 40-0 and 40-15 down to save service games in the second set, either side of claiming a decisive break, to condemn Norrie to his maiden first-round exit in five visits to Devonshire Park.
Meanwhile, compatriot Liam Broady was unable to mark his return from injury with victory as he was beaten by Japanese qualifier Yoshihito Nishioka.
The 30-year-old had been sidelined since March after his comeback from an ankle issue was delayed by sustaining concussion when he hit his head on a car boot in a bizarre accident.
Broady, who has reached the third round of Wimbledon in each of the past two years, was a break up in the second set before succumbing to a 6-3 6-4 loss.
Giles Hussey made the most of Kei Nishikori's late withdrawal from the tournament by upsetting Argentinian world No32 Mariano Navone to claim his first ATP Tour win.
After former US Open finalist Nishikori pulled out due to a right ankle injury, world No359 Hussey returned as a lucky loser and completed an impressive 6-4 6-2 win in an hour and four minutes.
Reigning Wimbledon boys' singles champion Henry Searle was unable to capitalise on his second chance.
Following the withdrawal of Spanish eighth seed Alejandro Davidovich Fokina due to back pain, the 18-year-old went down 6-3 6-2 to Italian Lorenzo Sonego.
"I'm shaking, I don't know if you can tell," 27-year-old Hussey said following victory over sixth seed Navone.
"I just came out here and wanted to enjoy it. I was sat there 45 minutes before the match and didn't know I was going to play today.
"I really didn't know much about Mariano but I knew that he's played predominantly on clay so I thought if I could come out here and just swing and go for my shots and try and rush him that that could be the best plan and, luckily, it all came off."
Elsewhere, fellow Briton Paul Jubb claimed his first ATP Tour win by defeating German Maximilian Marterer at the Mallorca Championships.
The 24-year-old, who has received a Wimbledon wild card, progressed to the last 16 with a 6-1 6-2 success after coming through qualifying.
