In 2008 he represented Vic Country at the 2008 AFL Under 18 Championships, was named in the TAC Cup team of the year on the wing and also selected in the AIS/AFL Academy.
In 2009, he captained the AIS/AFL Academy squad in their annual tour and was in the leadership group for Vic Country at the 2009 AFL Under 18 Championships.
Stevens was also invited to and attended the annual AFL Draft Camp at the Australian Institute of Sport in Canberra in October 2009 but did not participate in much of the testing as he was undergoing rehabilitation from osteitis pubis sustained mid-season.
Stevens requested a trade to the Western Bulldogs after the Eagles' 2012 season ended, wishing to return to his home state of Victoria and rejoin former Gippsland Power teammate and friend Clay Smith.
[3] On Monday 23 July 2018, Koby Stevens announced his retirement from football, with the 27-year-old unable to overcome his persistent concussion.