Gray made the comment following Wednesday’s 3-2 defeat to the Rams at the IPro Stadium in the Championship on Saturday.
“Derby are a good side and I think they will get promoted,” the 54-year-old told BBC Sport.
Will Derby County get promoted?
The 3-2 comeback win against the Owls means that Derby are now at the top of the Championship table with 62 points from 32 matches.
Steve McClaren’s side are currently two points clear of second-placed Middlesbrough and three ahead of Bournemouth, who are third.
Derby have arguably the best and most balanced team in the Championship, and have been pretty consistent throughout the campaign.
Given the competitive nature of the Championship, no one can say for sure that Derby will finish in the top two, but they have a better chance than the other challengers of doing so.
Against Wednesday, the Rams went behind twice, but they showed resilience and determination in staging a comeback victory.
It was also Derby’s first victory in four competitive matches, and one suspects that they will now put together a run of positive results.