Posted 26th July 2016 at 02:28 pm
A versatile attacking midfielder who can play through the centre or out on either wing, O'Sullivan is another player who has come through the Rovers Academy to be pressing his claims with the first-team.
One of the stars in the Under-18s run to the final of the FA Youth Cup in 2011-12, Dublin-born O'Sullivan made his Rovers debut at the end of 2012-13 as a second half substitute in the final game of the Championship season against Birmingham City.
An injury at the start of the 2013-14 campaign set O'Sullivan back, but he gained valuable first team experience on loan at Southport, before linking up with John Coleman a second time with a successful spell with Accrington the following season.
January 2015 saw the midfielder make the step up to League One at Barnsley, making eight appearances for the Tykes before returning to Ewood to feature twice at the end of the season.
Capped for Ireland up to Under-21 level, O'Sullivan had a month at Rochdale last season, before spending six months at fellow League One side Bury.