Britain's 23rd best tennis player, Marcus Willis, will make his Wimbledon debut after coming through six qualifying matches.
The 25-year-old has been spending his time coaching and last played a tournament in Tunisia in January.
Ranked 775 in the world, he had to come through three matches at last week's pre-qualifying event just to earn his spot at Roehampton.
There, he claimed his first top-100 victim by beating Japan's Yuichi Sugita, followed up with a win over former French Open junior champion Andrey Rublev and then clinched his spot in the main draw on Friday with a 3-6 7-5 6-3 6-4 victory over Daniil Medvedev.
The young Russian, ranked 228, took the opening set but Londoner Willis hit back for the most significant win of his career.
The left-hander has never previously played a tour-level match and is now guaranteed to pocket at least £30,000 in prize money.
Willis' success took the number of British players in the main draw to 15.
Meanwhile, British No.3 Kyle Edmund is set to earn a place in Great Britain's team at the Rio Olympics after a number of withdrawals among eligible men from other countries.
Edmund must now appeal to the International Tennis Federation because he has not played in the required three Davis Cup ties in the last four years.
The Yorkshireman's only appearance so far came in last year's final against Belgium, but his appeal should be a formality because he has been available throughout and has twice been forced to withdraw through injury.
Edmund wrote on Twitter: "Delighted to say (subject to successful appeal to ITF re DC eligibility) I have a place in #Rio2016. Fingers crossed!"
He will join Andy Murray, Jamie Murray, Johanna Konta and Heather Watson in Britain's team for Rio.
The leading 56 eligible players in the singles rankings on June 6 qualified for the Games, with no more than four from any one country.
Edmund was ranked only 84th on that date - he has since climbed to 68th - but a steady trickle of withdrawals brought him into contention.
Edmund will play France's Adrian Mannarino in the opening round at Wimbledon on Monday.