He was educated at Harrow School and Pembroke College, Cambridge.
In 1906 he began playing for MCC and also appeared for WG Grace's XI that summer.
Magnay was a right-handed batsman and played 21 innings in 12 first-class matches at an average of 14.66 and a top score of 73.
[2] He was also a member at Brokenhurst Manor Golf Club in the New Forest, and won the 1924 Hampshire, Isle of Wight and Channel Islands Amateur Championship, at Southampton's Stoneham Golf Club.
[4] He served in the First World War, was awarded the Military Cross and reached the rank of major.