[2] Doncaster began riding for the Ipswich Witches during the 1982 British League season.

[5] His good form continued and by 1985 was considered one of the league's leading riders, during 1986 he recorded a 10.38 average.

[6] Ipswich dropped down to the second tier National League in 1988, resulting in Doncaster joining the Reading Racers, where he topped the team averages.

Doncaster finished equal on 12 points with countryman Simon Wigg who defeated him in a run-off for second place.

After 1997, his average had dropped to around the six mark and he took a break from conventional speedway to concentrate on longtrack.