Having conceded an early goal at Sixfields, Nottingham Forest fought back to win the game 2-1 thanks to strikes from Chambers against his former club and McGugan.
Over 600 Reds fans were in attendance at Northampton and saw new signing Jonathan Greening in action for 70 minutes.
It's now back to their travels for Steve McClaren and his men, who face VFB Stuttgart in Germany at the weekend.