Sydney FC have received a hit to their A-League Men goal difference and a $5000 fine after being found to have broken league regulations.
The Australian Professional Leagues (APL) issued Sydney with a show cause notice regarding the make-up of its substitutes bench for three games in February and March, specifically for not having enough players below a certain age.
Teams are allowed to have seven players on the bench but under the "U23 rule" but to do so, at least three must be eligible to play for the Australian national teams and have been born on or after 1 January 1998.
The Sky Blues were found to have breached the rule in their 1-0 loss to Western United on March 23 and their 2-1 loss to Melbourne City on February 26.
They also didn't include enough under-23 players in their 2-0 loss to Western Sydney on March 5.
But in a quirk, the APL conceded their own match commissioners should have picked up on the initial breach.
They therefore didn't find Sydney guilty of a breach against Western Sydney "in recognition of the delay in identifying the initial breach."
"These rules were put in place to ensure young Australian players receive as many playing opportunities as possible, and so it's important that we ensure they are observed," A-Leagues commissioner Greg O'Rourke said.
"It's incumbent upon clubs to be fully aware of the eligibility requirements, however we acknowledge that if this had been picked up sooner then any subsequent breaches may not have happened.
"In the circumstances we deem a fine of $5000 is appropriate."
As a result, United's 1-0 win over Steve Corica's side becomes a 3-0 victory, as does City's 2-1 win, boosting both clubs' goal difference by two.
In total, the breaches cost Sydney four goals' worth of goal difference: three goals against and one goal for, which could prove crucial given their finals spot is in jeopardy.
Sydney did not receive any punishment for the Wanderers game, with that scoreline unaffected.
The Sky Blues accepted the sanction for what they considered an "oversight".
"The club has acted quickly to put in place a more thorough process of checks to ensure no such sanction should be awarded in future," Sydney said in a statement.
"Sydney FC has also requested APL strengthens its own processes so discrepancies are picked up earlier, rather than by rival clubs, with errors relayed by the game day Match Commissioner once the team sheets are submitted and the relevant APL department before the next game."
Any Johnny Warren Medal votes awarded to Sydney players for the matches will remain valid, while Milos Ninkovic's goal against City will still count towards his golden boot tally or qualify for goal of the year.
