Beginning his professional career with Southampton in the Premier League where he made three appearances, Blayney had additional loan spells with Stockport County, AFC Bournemouth, Rushden & Diamonds and Brighton & Hove Albion (twice).
He then spent just over a year with Doncaster Rovers before having successive quick spells with Oldham Athletic and Bohemians, before returning to his native Northern Ireland with Ballymena United.
Blayney, who was then behind Antti Niemi and Paul Smith in the team's pecking order went on loan to Rushden & Diamonds[7] and Brighton & Hove Albion.
[11] Blayney started off as first choice goalkeeper at Belle Vue stadium, but fell behind Ben Smith and Dane Jan Budtz in the pecking order after an ankle injury.
[13] In February 2007, Blayney joined League One side Oldham Athletic, until the end of the 2006–07 season, after impressing in a reserve team match.
[14] Blayney made his début for Oldham Athletic in a 1–2 home defeat against Bournemouth, after first choice goalkeeper Les Pogliacomi was suspended.
[15] On 7 August, Alan Blayney joined Irish side Bohemians on a short term deal to provide cover for first choice goalkeeper Brian Murphy.
[19] Following his loan spell at Ards, Blayney left Linfield at the end of the 2013–14 NIFL Premiership season to sign for 2013–14 Irish Cup winners Glenavon.