John Textor, who retains his shareholding in Palace and is also the owner of Lyon, is at the center of this issue. UEFA's multi-club rule prohibits a person from owning shares in multiple European clubs.

"We're extremely disappointed," Parish said. "This is a difficult day for football. We feel it's unfair that we've been locked out of a European competition due to a technicality."

Parish emphasized that Crystal Palace is not part of a multi-club setup and does not share staff with Lyon. He believes the club was unfairly affected by a rule not intended for them.

"We've shown that John Textor has no influence over our club," Parish stated. "This decision is unjust, and we will appeal it to the court."

It's worth noting that Textor has agreed to sell his 43% stake in Palace to Woody Johnson, but the deal is yet to be finalized.