Peterborough United's play-off hopes damaged at the home of their local rivals

Losing at Cambridge United for the first time in a Football League match for 25 years was bad enough, but to be outplayed by a team who started the day third from bottom of the table was deeply worrying.

Posh appeared flat for most of the contest and after falling behind on the stroke of half-time there was little response. Cambridge goalkeeper Dimitar Mitrov didn’t make his first save until midway through the second-half and 60 seconds later the home side had wrapped the game up with a second goal.

Posh missed a great chance to pull a goal back immediately and should have won a penalty late on, but pointing a finger at referee Ross Joyce, who pointed only one way for the entire second-half, for the 2-0 defeat would be a mistake.

How much damage this day does to longer-term ambitions will be seen later today and then in the next few days. For now Cambridge deserve the credit for maintaining an impressive record in this fixure pretty comfortably, while Posh must retreat and lick their wounds after a first defeat in seven League One matches.

Posh were forced to change a winning side as injury ruled Joe Ward out of the game.

Harrison Burrows returned to the starting line-up with Kwame Poku moved into a wide position.

Joel Randall and Ben Thompson were restored to the substitutes’ bench, but young forward Ricky Jade Jones was another injury absentee.

Cambridge had plenty of useful experience in their side including former Posh promotion hero Ryan Bennett at centre-back. Lloyd Jones, who won the first derby for Posh in October, was not involved, but there was a place at right-back for former Peterborough Sports loanee Liam Bennett.

As expected with so much riding on the game for both sides it was a tense affair with few clearcut chances in the first-half.

Ephron Mason-Clark lashed the best Posh opportunity wide after latching onto a long ball from Frankie Kent seven minutes before the break, but Cambridge played with the greater urgency and were worth the lead they gained in the second minute of added time.

One would imagine Posh boss Darren Ferguson had harsh words ready for his side even before Harrison Dunk sidefooted home from close range when unmarked at a corner.

Posh had been laboured in possession and offered little apart from Jack Taylor’s midfield probing and Mason-Clark’s efforts.

Jonson Clarke-Harris shot first time just over the crossbar from 20 yards after a decent move in the fisrt 10 minutes and the one corner they won in the opening half was allowed to travel a long way before the ball was cleared.

The home side many more penetrations into the Posh area, but Ronnie Edwards and Frankie Kent made strong blocks.

Otherwise Cambridge wasted opportunities with poor crosses, until the 47th minute and that match-defining corner, as the first-half ended with neither ‘keeper having made a save and yet Posh were behind.

Posh tinkered with formations and personnel in the second-half, but nothing worked.

Cambridge made all the early running with a back-post header from Harvey Knibbs and a Jack Lankester strike causing alarm. Lankester also fired over from a free kick as Posh couldn’t get going and became increasingly ragged.

A rare good passing move ended with Mitrov saving from Ogbeta, but hope was extinguished inside 60 seconds as a cross from Liam Bennett was swept home via the inside of the post by the in-form Sam Smith.

A fine cross from Ogbeta a minute later should have led to a goal for Taylor, but he headed down and straight at Mitrov.

There was little encouragement after that despite plenty of possession, although how Joyce, who let Ryan Bennett avoid a caution for a blatant trip, didn’t award a penalty when substitute Jubril Okedina bundled Clarke-Harris over from behind four minutes from time was quite remarkable.

But Posh really shouldn’t be relying on outside help to get results at places like this against teams like this.

Not for the first time this season and immediate response is now needed.

Posh: Will Norris, Nathanael Ogbeta, Frankie Kent (sub Dan Butler, 57 mins), Ronnie Edwards, Nathan Thompson (sub Josh Knight, 75 mins), Jack Taylor, Oliver Norburn (sub Joel Randall, 82 mins), Ephron Mason-Clark, Harrison Burrows (sub Hector Kyprianou, 57 mins), Kwame Poku (sub Kabongo Tshimanga, 75 mins), Jonson Clarke-Harris

Unused subs: Will Blackmore, Ben Thompson.

Cambridge: Dimitar Mitov, James Brophy (Fejrir Okenabhire, 81 mins), Ryan Bennett, Michael Morrison, Liam Bennett, James Brophy, Harrison Dunk, Conor McGrandles, Jack Lankester (sub Jubril Okedina, 81 mins), Harvey Knibbs (sub Shilow Tracey, 77 mins), Sam Smith (sub Joe Ironside, 85 mins)..

Unused subs: Will Mannion, Steve Seddon, George Thomas

Goals: Cambridge – Dunk (45 + 2 mins), Smith (67 mins).

Cautions: Posh – Kent (foul), Taylor (dissent), Tyler (goalkeeping coach, dissent),

Cambridge – Lankester (foul).

Referee: Ross Joyce 6.

Attendance: 7,711 (1,473 Posh).