The side claimed a comfortable victory over Albion Park, however they will not feature in this week's grand final, with the South Coast Cricket Association instead progressing the Eagles through to the decider. 

Albion Park will now take on Lake Illawarra, who defeated Jamberoo in last week's semi-final.

South Coast Cricket president Grant Tilling said all teams had been warned leading up to the finals not to use ineligible players and while unfortunate, the association had no choice but to enforce the rules. 

"They played a non-qualified player," Tilling said. "It is the club and captain's responsibility to ensure all players that take the field in semi-finals are eligible to play."

Read more: Oak Flats looking to complete remarkable turnaround 

To qualify for finals, players must meet two criteria. They must play eight games during the season and play four of the last eight games for their specific team. 

The player in question, Neil Teasdale had played five games during the latter half of the season.

Kookas captain Terrance Insley said the error was made as a result of a misunderstanding and is disappointed with the decision. 

"There was a misunderstanding," Insley said. "I asked about eligibility and was only told you had to play four of the last eight. We had 12 players, if I knew he was ineligible, I wouldn't have played him.

"They weren't going to beat us, I thought common sense would prevail. It's tough to swallow, we've tried all avenues, there's nothing we can do now."

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