The pair were in a taxi in Adelaide's central business district in the early hours of Monday morning when they were stopped by police at 5.15am CDT and found with an illicit drug, understood to be cocaine.

Police didn't charge the duo, instead referring them to counselling under a drug diversion program, but Crouch and Stengle both face potential fines and other sanctions from the Crows and the AFL.

"I am ashamed, embarrassed and disappointed in my actions," Crouch wrote in an apology on Instagram on Thursday.

"Firstly, I want to apologise to the Adelaide Crows supporters. They support me and they support the club so well and I know that as a sportsperson there will be those that look up to me as a role model.

"I would like to apologise to the playing group at the Adelaide Football Club, who have given me the opportunity since the age of 17 to live my childhood dream of being an AFL footballer."

Crouch, 26, also apologised for the impact his actions had on his partner, family and friends.

"I have made a big mistake. I hope and trust that it does not define me. This is not who I am," he said.

"I will strive to be a better person and know that I need to regain the respect of those who I have let down."

Stengle then also apologised over Instagram on Thursday afternoon.

"I have let down my family, friends, the Adelaide Football Club and the AFL community," he wrote.

"To the loyal Crows supporters, members, sponsors and to the young boys and girls who aspire to be a footy player and look up to me, I have let you down. I am sorry.

"There is no excuse for my behaviour.

"I will now work hard to try and earn your trust back and repay the faith and the love you have shown me."

Adelaide's 2019 club champion, Crouch is a restricted free agent and is considering offers from rival clubs.

On Tuesday, Adelaide chief executive Andrew Fagan said the Crows' investigation into the drugs bust and negotiations with Crouch about his playing future are "two separate processes".

Stengle was previously suspended by the Crows in April for four AFL games after he was caught drink driving and driving an unregistered car.

The 21-year-old was due to appear in Adelaide Magistrates Court next month to answer those charges.

He signed a contract extension until the end of 2022 in August.

Australian Associated Press