A right-handed batsman who bowled right-arm medium, Rosier made his Minor counties debut for Bedfordshire against Cambridgeshire in the 1968 Minor Counties Championship.
He played 22 matches of Minor Counties cricket for Bedfordshire from 1968 to 1973.
[3] He made his List A debut against Dorset in the 1st round of the 1968 Gillette Cup.
He made 2 further List A appearances, against Hampshire in the 2nd round of the same competition and Lancashire in the 1973 Gillette Cup.
[7] He also made List A appearances for Minor Counties South, playing 2 matches in the 1973 Benson & Hedges Cup against Hampshire and Somerset.