Thornton was a 56th minute substitute in the Cobblers 1-1 draw with Burton Albion at Sixfields.
Elsewhere, Gary Madine played the whole ninety minutes for Carlisle United in their 2-2 draw with Leyton Orient. It is the first time that he has played a full game since returning to the Cumbrians following his trial at Coventry City.
Gary McSheffrey started for Leeds United in a 2-0 win against Colchester United and Patrick van Aanholt made his Newcastle debut against Leicester City.