The England Under-21 international drew praise from Sir Alex Ferguson for his performance but it came at a cost with United forking out another £100,000, as part of the deal that took the midfielder to Old Trafford.
The original down-payment to City was £350,000, but another £400,000 has been forthcoming due to the amount of matches Greening has played for The Red Devils.
"Jonathan Greening was marvellous," said Ferguson, after the 21-year-old teed up the goal for Dwight Yorke, and was extremely unlucky not to win a penalty when he was felled by Thomas Sorensen.
