The 27-year-old Troon man joined compatriot Liam Johnston as a winner on the second-tier circuit this season after signing off with a one-under-par 71 at St Mellion, where the event was presented by Modest! Golf Management.
He finished with an eight-under 280 total, winning by a shot from South African JC Ritchie (69), with Englishman Matthew Baldwin (76) one further back in third spot.
“It feels absolutely amazing,” said Walker, who had started the day three shots off the lead. “To win this week far exceeds any expectations I had and it is absolutely brilliant.
“At the start of the season, things weren’t going that well but, over the last few months, I have started to turn things around.”
Worth £36,800, the win lifted the 2019 Walker Cup player 43 spots to 20th in the Road to Mallorca Rankings with only two events remaining.
The English Trophy starts on Thursday at Frilford Heath before the campaign concludes with the Grand Final in Mallorca next month.
If Walker can cement a top-20 spot, he’ll join Bob MacIntyre, Grant Forrest, David Law, Callum Hill, Ewen Ferguson and Craig Howie in securing a step up to the main tour over the past few years.
“For most of the year I had been battling what kind of playing status I was going to have but the results have been much better in recent weeks,” he said. “A win at this time of the season has put me into a great position on the rankings.”
Walker looked to have dented his title hopes with a double-bogey 7 at the 12th then following that with a bogey at the par-3 14th.
But, after moving into a share of the lead by making a 3 at the 17th, he hit one of the best shots of his life at exactly the right time from 165 yards over water at the last to no more than four feet.
“On the 18th, I didn’t realise I was in contention until I saw the leaderboard,” admitted Walker, who is in his third season on the Challenge Tour, having finished 88th in 2020 and then 118th in 2021.
“I realised a birdie would probably be good enough to win so I just had to be aggressive and go for it. I hit a great drive and then I struck my approach shot absolutely perfectly and luckily it was nice and close.
“Standing over that putt was definitely the most nervous I have ever been in my life. I only took one practice stroke and I normally take two because I was just thinking I need to hit this before I seize up.”
On the back of his success, Walker, who is in the same Bounce Sport stable as recent Italian Open winner MacIntyre, could jump inside the top 600 in the Official World Golf Ranking, for first time.
“My mum and dad were here today which was absolutely brilliant,” he smiled. “They like to come to the British events and I’m glad they were here to see this.”