Peterborough were thrashed 4-0 by Bradford in League One yesterday.
It was the Yorkshire sides first ever win at London Road.
Posh are now 10th in the table with the same number of points as Bradford who are now one place behind them.
Meanwhile Northampton have made it seven straight wins and remain five points clear at the top of League Two.
The Cobblers brushed aside play-off hopefuls Leyton Orient 4-0 yesterday.
In the National League North Corby won 2-0 at home to Tamworth but Brackley lost 3-2 against Nuneaton.
In the Southern Premier Kettering won 2-0 at Chippenham and in the Southern Division One Central AFC Rushden and Diamonds went to Fleet where they drew 0-0.