Result: Darren Ferguson celebrates Peterborough milestone with big win over Birmingham

On the day Darren Ferguson broke the record of most games managed by a Posh boss, his 492nd match at the helm was certainly among the happiest as it came complete with a 222nd win - and few of the previous 221 have been as emphatic or essential as this triumph.

The form book went out of the window as a Posh side, who had slumped to four successive Championship defeats, dominated a City team previously unbeaten on their travels.

Ferguson's men made the perfect start inside the opening minute - albeit with a helping hand from the visitors as stretching City skipper Harlee Dean could only steer a Siriki Dembele cut-back past his own goalkeeper Matija Sarkic with 58 seconds on the clock.

Ferguson handed a first league start to David Cornell in goal with regular number one Christy Pym missing due to illness but the Welshman was rarely pressed into action by a City side featuring full debutant Troy Deeney in their attack.

The former Watford man did force Cornell into a routine stop with the second of two headed efforts around the midway point of the opening period but there was considerably more threat posed at the other end.

Dembele saw a shot well blocked seconds after Jack Taylor danced round the onrushing Sarkic only to be carried too wide to be able to get in a shot at a gaping target.

But Posh didn't have to wait long to double their advantage as referee Jarred Gillett pointed to the spot when Jorge Grant was brought down by Ryan Woods after being sent clear by a fine Dembele pass.

Jonson Clarke-Harris had no trouble in tucking away his second penalty in three games by sending Sarkic the wrong way in the 35th minute.

He should have been celebrating again moments later only to fluff his lines with just Sarkic to beat but Posh were well in command.

Birmingham boss Lee Bowyer rolled the dice with a double change at the break and it almost reaped instant reward with Woods being denied by Cornell from a tight angle.

But City were again on the receiving end as the crucial third goal arrived five minutes into the second half with chief Posh tormentor Dembele again doing much of the damage.

He tricked his way inside and picked out Grant, who claimed his first Posh goal with a precise finish from the edge of the box in the 50th minute.

The outcome was put beyond doubt when City midfielder Gary Gardner saw red in the 65th minute for a shocking challenge on Nathan Thompson.

That left Posh to comfortably see out a second success of the campaign with a terrific Cornell stop late on denying Deeney a consolation for the well-beaten Blues.