Leicester-born Clay played for numerous local sides before penning a deal with Fosse in April 1911. He made his debut later that year, against Bradford Park Avenue, and took the place of Billy Henry, who'd moved on to Manchester City.

Clay was an unflappable full-back who impressed in a Fosse side who were struggling at the time. A more cultured defender than most at the time - he liked to pass the ball out of defence rather than 'hoof' it. His performances were so good in entertaining FA Cup clashes with Tottenham Hotspur in 1914 that Spurs went on to sign both him and Harry Sparrow.

At White Hart Lane Clay won the Second Division Championship, FA Cup and was runner-up in the League Cup.He spent the best part of his career with Spurs - playing over 350 games for them - and finished his career as a player-coach with Northfleet. He was one of the first Leicester-born players to play for England.