A close source has shed light on the pair's relations before a Brisbane Lions WAG allegedly discovered them in a car.
Lachie Neale and Tess Crosley's affair was going on for three months, an insider has claimed.
The pair's relationship was allegedly uncovered by a Brisbane Lions WAG, who discovered them in a compromising position in a car, the Herald Sun reported.
And, according to Daily Mail, the incident was not a one-off indiscretion.
A close source told the publication that the former Lions captain, 32, and Crosley, 30 - who was previously close friends with his wife, Jules Neale, 35 - were engaged in a three-month tryst.
Given that news of Lachie and Jules' split hit headlines mid-December, this means the alleged affair began just before the 2025 AFL Grand Final, where the Lions sensationally beat the Geelong Cats.
Despite the insider information, a source within the AFL star's camp has shut down the proposed timeline, insisting that the car encounter was a singular incident.
Lachie has since stepped down as co-captain of the Lions and Jules has returned to her home in Perth with her children, Piper and Freddie.
The former hair salon owner took to social media in December to write that she was dealing with an "unimaginable betrayal".
"I want to make it very clear that I am not ‘working through’ anything," Jules said in the explosive post.
"All I can do now is to heal and do what’s best for my children.
"Thank you for the love and support."
Lachie has since stepped down as co-captain of the Lions and Jules has returned to her home in Perth. Picture: Chris Hyde, Getty Images
Lachie has addressed the Brisbane media and apologised for his actions, saying he is "deeply sorry for hurting those closest to him".
"I can confirm, with regret, Jules and I have now separated," he announced.
"I accept this is a consequence of my own actions, and I need to focus on rebuilding that trust with Jules, as the future wellbeing of our children remains our number one priority.
"I am extremely disappointed in myself, and I have put plans in place to do the work on myself so that I can be the best version of myself moving forward."
The two-time Brownlow medallist then revealed that, while being co-captain was a "huge honour", it was time for the club to "move forward with a fresh start".