Gap Connah's Quay have been found guilty by a Football Association of Wales Disciplinary Panel of fielding an ineligible player.
The club have been deducted a point and fined £250 for fielding Lee Davey as a substitute in the Welsh Premier match against Carmarthen on 5 January.
Davey had previously played for Colwyn Bay and Conwy Borough this season
While Davey was entitled to register for Quay, participating for three teams in one season is not permitted.
"Gap Connah's Quay has seven business days in which to appeal the decision. The club is perfectly within its rights to appeal the decision," said the Welsh Premier League in a statement.
"The Corbett Sports Welsh Premier League is aware that this may impact the beginning of the Second Phase of the Corbett Sports Welsh Premier League."
In response Connah's Quay said they would be making a statement in due course.
Mark McGregor's side secured a place in the top six ahead of the Welsh Premier League's mid-season split with a 6-3 win at Bala Town on Saturday.