Harold was born in Silverton, near Exeter, in 1904 and used to play with a rag ball during his lunch break at the local paper mills. This helped him develop both hard and accurate shooting – skills that quickly brought him to the Grecians after playing for Silverton United. He scored twice on his debut for City Reserves in 1923/24 and was their leading scorer the following season with 24 Southern League goals. He made his Football league debut against Swindon Town in 1924 and really made his mark in the following seasons especially 1926/27 when he was City’s leading scorer with 25 goals in 36 League and cup appearances.Towards the end of that season Blackmore played against Bolton Wanderers in a benefit match and scored twice. Bolton were so impressed that they signed him for £2,150 and he joined former Grecian Dick Pym in the Trotters’ all-star line-up. The move was a great success with Harold leading Bolton’s Division One scoring charts for three successive seasons as well as scoring in the FA Cup Final at Wembley when Bolton beat Portsmouth 2-0 in 1929. After scoring 111 goals in 153 games for Bolton, Blackmore signed for Middlesbrough in 1932 and later played for Bradford Park Avenue and Bury. After retiring, with a career record of 201 goals in 309 League games, he returned to Exeter and ran a butcher’s shop. He died in 1989.