The Stags won the toss and elected to bat, but some excellent bowling from openers Richard Banham and Graham Porter put Ashtead immediately under pressure and caused the fall of some early wickets – Gary Martin (bowled for six), Jamie Powell (lbw for five) and Viv Paver (lbw for seven) – leaving the Stags 22-3.
However, that situation is often where Ashtead excel, and so it proved, with a strong 50 partnership between Andy Michael and Chris Douglas steadying the ship, and after the demise of Michael (lbw for 19), Brendan O'Connell came in and the pair attacked the bowling more strongly.
At lunch, Ashtead had reached 95-4 off 31 overs and were in much better shape.
Despite the early loss of Douglas after the interval (caught for 35), Ashtead continued their attack and forged ahead with O'Connell, now helped by David Burton, another determined batsman, and together they put on another 50 runs before the loss of O'Connell (caught for 43).
That was quickly followed by the wicket of Burton (run out for 24), but John Vaughan-Davies and Tom Deighton, the two new batsmen, continued to push forward and keep the scoreboard ticking over.
When Deighton finally succumbed by intensive pressure from top spinner Tim Monteleone (caught for 18), the Stags had passed 200 and were looking to set a competitive score.
Eventually, Ashtead were bowled out for 215, giving Wimbledon 55 overs to make the runs.
After the short interval between the innings, there was immediate success for the Stags on the very first ball when Graham Grace chipped straight to Vaughan-Davies who was waiting at square leg for an easy catch.
That brought Wimbledon skipper Neil Turk to the crease, to partner Steven Hobson, and the pair provided insurmountable resistance for the Ashtead bowlers.
At tea, Wimbledon were 74-1 and cruising.
Hobson and Turk both made their 50s soon after, and when the curtain fell on the game, both had made well-deserved centuries, in a mammoth 219 stand.
However, saying just that would do injustice to the commitment and dedication that Ashtead showed in the field.
Even though the two batsmen were at ease, hitting 38 boundaries between them during their partnership, heads were held high and there were some astounding stops and dives throughout the innings.
In the end, Wimbledon claimed a straight-forward nine-wicket victory that sees them climb into the top three in the standings, as Ashtead slip towards the middle-order.
Next week Ashtead will look to get back to winning ways as they take on Sutton, a team that has been struggling for form of late, including a hefty defeat at the hands of Sunbury.The game marks the second fixture in a double-header for the two sides, as both clubs meet at Woodfield Lane for the Surrey Championship T20 quarter-final on Thursday.