The 20-year-old Saxton had eight birdies in 34 holes to finish off the 17-year-old Fleetwood, attempting to become the youngest winner.
I felt quite relaxed, Saxton said. Of course youre going to feel a little pressure over the last few holes, but I just had to stay focused whatever happened.
Even when youre three holes ahead you can still lose.
Fleetwood praised Saxton.
Tee to green he was much better than I was, Fleetwood said. I cant be disappointed. I did better than 286 other golfers but I would really like to have won.
Saxton, who earned spots in the British Open at Birkdale and next years Masters as long as he remains an amateur, is the second Dutch winner, following Rolf Muntz in 1990.