The Chinese international, guesting for the Reds from Royal Antwerp, produced a composed piece of finishing to calmly convert a Darren Fletcher pull back from eight-yards just as a stalemate looked likely.
Sir Alex admitted in Durban that he was waiting on Dong to play enough games for his country, or to gain European citizenship, so that he could bring the youngster to United permanently.
You can see why. The 21-year-old replaced Ole Gunnar Solskjaer at half-time of this game and twice tested Chief’s goalkeeper Rowen Fernandez and was denied a near certain goal by Scholes just minutes before his eventual winner.
His goal was to settle a game that the Reds found considerably harder going than they had the 4-0 hammering of the Orlando Pirates three days earlier.
The first half was every bit as tight as the United manager had anticipated, with the Chiefs far better organised than their fierce rival.
There was none of the kamikaze defending from the local side that the Pirates had displayed. Nor did their midfield allow Paul Scholes and Ryan Giggs to dominate proceedings quite the way they had in the first game.
Another difference was the lightning start that the Reds had made in Durban, where Ole Gunnar Solskjaer had given them the lead inside five minutes.
In fact, United’s first genuine opening took seventeen-minutes to arrive, again Solskjaer was involved.