The 15-year-old already had the Lincs Trophy Day Series title wrapped up, having won all four of the event races, and completed the county double with victory in Benniworth.
The triumph was the perfect build-up for next weekend’s British Championships where the Alford rider has earned himself a front row grid slot thanks to his national ranking of eighth.
The penultimate County League event was held on the unforgiving hilly, muddy course at Benniworth where Windsor knew a win would prevent the title race going to the last race of the season at Bardney.
Mindful of the fact his closest rival, from Bourne Wheelers, needed to win both races to tie, Windsor arrived with plenty of motivation.
A nervy race of cat and mouse was expected, but he had his own race plan, and from the whistle shot off up the long incline, setting a brutal pace.
He immediately built a 20-metre lead, and with no response coming from the pack, Windsor had a 40-second lead by the first bike change, halfway round the opening lap.
Showing relentless energy and stamina, he kept pushing on and by his second bike change on lap two the championships were at his mercy, with a 90-second cushion.
Each lap saw a change onto a fresh clean bike and on lap four, 25 minutes into the race he took the bell with a three-minute lead from his nearest rival.
With such a lead he could have ran the remainder of the race, and took the chequered flag after 31 minutes of punishing cycling more than four minutes clear.
Windsor had warmed up for the race 24 hours earlier at Mansfield where he claimed a strong second place in a high-quality field.
Riding against the Midlands champion, a European standard mountain biker, as well as two top 10 national riders, Windsor rode his race of the season to push the champion all the way, leading for two laps before ultimately being pipped to the line.
* The previous weekend, Windsor raced at Matlock in the Notts and Derbyshire League against a strong field including the British number one, and the Midlands champion.
A difficult course in almost impossible conditions saw the Lincolnshire rider change bikes every half-a-lap and finish a disappointing fifth out of 21 riders, with the conditions forcing him to run almost 40 per cent of the race.
The following day he was beaten into second place in the Lincolnshire League at Scunthorpe by his Bourne rival.
The two riders burst clear with a blistering start, gradually leaving the rest of the field way behind.
Having had the better of their previous encounters, Windsor continually attacked, but each time the Bourne rider responded and closed the gap.
It became obvious the flat, hard grass surface was better suited to his rival who would not be shaken off, and on the final bend the Bourne Wheeler exercised his track experience and produced a powerful sprint to take the chequered flag by eight seconds.