The highly-rated young striker has been chased by Premier League clubs Leicester City and Everton.
However, it looks like the Bhoys will beat the Premier League duo in the race to sign the 18-year-old who has made 17 appearances for the club this season.
With Wigan collapsing into administration, the club would be looking to sell some of their players, and Gelhardt could be among them.
Celtic were keeping a close tab on the player for a while, and it seems they are lining up an offer for the talented young striker.
The report claims that the Bhoys are ready to pull out all the stops as they look to blow Leicester and Everton out of the water. At the same time, they understand it will take a major bid and contract offer to lure the England Under-18 international.
While a move to Everton or Leicester could be attractive for the youngster, he could get a better chance of playing regularly if he joins the Bhoys.
Gelhardt is an exciting young talent. Everton could be interested in signing a striker this summer, but whether the Toffees will make a move for him remains to be seen.