The Sky Blues are close to agreeing a fee between $250,000 and $300,000 with the South Korean club for O’Neill, who is contracted until mid-2021 and has previously been linked with several clubs in the Championship.
It’s understood the combative 25-year-old fringe Socceroo has agreed personal terms on a one year deal, with an option for a second season.
He is expected to undergo a medical with Pohang on Monday.
O’Neill has made seven appearances this season, scoring one goal and claiming three assists.
Currently recovering from a knee injury which has already sidelined him for five weeks, he isn’t expected to be fit again until the last week of January.
Perth-born O’Neill has amassed 112 A-League appearances for Sydney across five seasons, winning two premierships, two championships and an FFA Cup.
Though considered one of the most accomplished midfielders in the competition, Sydney’s hierarchy believe they have adequate cover in Luke Brattan and the recently re-signed Paolo Retre, as evidenced by the table toppers’ four wins from five in O’Neill’s absence.
Recently home to fellow Australian Connor Chapman, Pohang were close to signing then-Sydney midfielder Josh Brillante this time last year prior to his subsequent move to Melbourne City.
They finished fourth in the K1 League last year, last winning the title in 2013. They have also claimed three AFC Champions League titles.
Sydney FC were contacted for comment.