Boss Southgate said: "I guess Wheater has surprised me, he has shown consistency.
"There are little things he will learn and improve on.
"But we couldn't have wished for him to do as well as he has or believed he has played in as many games as he has done this season.
"Woody and Manuel Pogatetz were the main partnership last year but David is challenging them.
"You have to consider he was at Darlington on loan last year.
"It is fantastic to see the kids progress. You can't really believe what we are dealing with here. And Rafa is telling me he has no money."