Hornsby's chances of breaking into the first team were very rare and he did not make his debut until May 1973 in the final league game of the 1972–73 season in a 6–1 defeat at Leeds United.
Hornsby was released by Arsenal at the end of Bertie Mee's reign as manager and he signed for Shrewsbury Town in May 1976 for £40,000.
In February 1978 Durban left to be manager of Stoke City and the following month Hornsby signed for Sheffield Wednesday in a £45,000 deal.
Charlton was giving his pre-match team talk and midway through turned to Wednesday midfielder Jeff Johnson and said, "You're up against the lad Hornsby, he's a very skilful player ...
On signing, Hornsby had said on local radio that he would score plenty of goals from midfield, his first came on 25 March in a 2–0 away win at Rotherham.
The 1978–79 season saw Hornsby finish as top scorer for Wednesday with 21 goals in all competitions including three in the FA Cup 3rd round marathon against former club Arsenal.
[4] Hornsby spent part of 1982 playing for the Canadian NASL team Edmonton Drillers but returned to England after they hit financial trouble and folded.
After a brief spell on loan at Chesterfield, Hornsby moved to Sweden in 1984 to play for IK Brage for a season, making 20 appearances and scoring 1 goal.