The Crows team were watching the SANFL game between Adelaide and North Adelaide, reports say teammates overheard him at the Crows’ quarter-time huddle talking about a North Adelaide player.
The 31-year-old was given the morning of due to the scrutiny and situation.
Training commenced at Adelaide Oval on Thursday without Walker, club officials previously indicated on Wednesday they would not stand him down.
Adelaide or the AFL are yet to release a statement following the allegations, with the league probing the situation after players were left 'disappointed' by actions from on of their leaders.
Walker is expected to play this weekend's Showdown against Port Adelaide.