 Danny Williams signed Horsfield to the Wiltshire club in 1969 for £17,500 (the club's record signing at the time), one of his last actions at the club.By the end of his first season he had become the club's top scorer with 22 goals.He took part in Swindon Town's European cup winning games scoring a hat-trick against AS Roma to win the 1969 Anglo-Italian League Cup and also the winning goal against SSC Napoli to win the 1970 Anglo-Italian Cup.