Struggling Northampton claimed a crucial victory over Doncaster, while Brighton made it three wins out of three at home by coasting past Millwall.
Dean Hammond broke the deadlock for The Seagulls with a penalty after 12 minutes. Dean Cox then made it 2-0 in the 19th minute and new signing David Martot clinched the points late on to take Dean Wilkins' side up to fourth.
After a tight first half, Ryan Gilligan fired Northampton ahead in the 50th minute. Andy Kirk netted a second 19 minutes from time.