City's U21 side defeated the Posh at CCS on Tuesday afternoon.
Match Report
The young Bluebirds returned from the international break to record a resounding victory over Peterborough United on Tuesday, keeping a clean sheet as they claimed all three points from a comprehensive performance.
From kick-off, City looked to be on the front foot, and after dominating early proceedings were quickly ahead thanks to Cody Twose's sublime finish inside the area.
Incisive, one-touch passing and dominance of possession provided City with a platform to build their lead on, and the tireless young Bluebirds continually tested the visitors before Roko Šimić doubled the lead five minutes from the interval, finishing well following some terrific build-up play down the length of the pitch.
Early in the second half, Peterborough had their biggest chance from a corner-kick, as they put the ball in the back of the net. However, the referee awarded a free-kick to City for a foul committed in the build-up.
Will Spiers subsequently set up the third goal of the afternoon, as he darted down the right before delivering a dangerous low cross towards Šimić, who stretched to finish on the half-volley, bagging a brace for the Bluebirds.
Having put in a resolute display in all aspects of play, with 10 minutes left the hosts added a fourth through substitute Cole Fleming, whose solo effort from 25 yards may be the pick of the bunch as it flew into the top left corner of the net.
With the final whistle blown, City had begun the final stage of the season with the best possible start, and now look ahead to next week's away fixture against Crewe Alexandra.
FINAL SCORE: CARDIFF CITY 4-0 PETERBOROUGH UNITED
Watch below with Cardiff City TV!