The U's were hit for seven as Preston progressed in the FA Cup.
It was 2-0 at half time but a three goal salvo at the start of the second half killed the game as a contest and two further goals made things worse.
It came after the U's had started the game brightly, and had probably had the better of the first twenty minutes - but it all went wrong after then as the hosts went goal crazy.
The focus now firmly turns to the league, with a big January coming up for Aidy Boothroyd's men.
Boothroyd made three changes to his starting line up, with Kevin Lisbie and John-Joe O'Toole not featuring in the eighteen man squad and Kem Izzet starting on the subs bench.
David Fox, Simon Hackney and Kayode Odejayi were the trio replacing them as the U's looked to cause an upset against Championship side Preston.
How much of a surprise could be debated with the U's sitting in the top four of League One and Preston sitting in the bottom half of the Championship, with only one win in their last ten matches.
They were also without a manager, having parted company with Alan Irvine following their final game of 2009. Robert Kelly, Irvine's assistant, was in temporary charge as the Preston Board considered their next move.
The game started with the temperatures hovering around freezing point but the U's started well, taking the game to their opponents.
A Simon Hackney cross just evaded Gillespie and Ifil and then Hackney had an effort from outside the box that flew wide.
Ben Williams saw his first action of the game after ten minutes and was more than equal to Carter's drive, palming away with his left hand. The rebound fell to Collins but the Preston centre half was offside as he scuffed the shot wide.
Some good build up play on the left saw David Fox drive his shot just wide in the eleventh minute but three minutes later, the home side opened the scoring.
They gained a corner on their right and Ross Wallace whipped in a left foot cross that Chris Brown headed past Williams' right hand and into the bottom corner of the U's net.
The U's wee having their fair share of possession but Preston were defending their box well and were restricting the U's to long distance shots.
Fox, Ifil and Wordsworth all had shots from outside the box but Wordsworth's was the only one on target, a deflection preventing it testing the home keeper.
Preston were coming more and more into the game and with Wallace pulling the strings, they extended the lead on twenty seven minites.
Wallace found Brown and the scorer of Preston's first turned provider as he held off Okuonghae and rolled the ball out to Sedgewick. Sedgewick tried his luck from the right and Tierney's block deflected the ball over Williams and into the net to give Preston a two goal lead.
Wordsworth then hit his free kick over the bar after being fouled himself and Gillespie was denied by a tackle after Joel Thomas's shot had fell to him in the box.
Thomas had replaced John White on thirty five minutes after the U's full back was caught heavily from behind by Carter.
Preston finished the half well and Williams had to be in the right place to save comfortably from Parkin a couple of minutes before the referee blew for the half time break.
The U's would have wanted to start the second half on the offensive but within seven minutes, found themselves 5-0 behind and out of the cup.
A long clearance found the head of Brown, his flick found Parkin and after cutting inside his marker, Parkin tucked his shot under Williams.
On fifty minutes, it was four as Parkin scored his second with a delicate lob and two minutes later, Brown made it five.
Good play on the right led to Brown hitting a left foot shot goalwards. It rebounded off the post though and hit the unlucky U's keeper and ended in the U's net.
There was a lull in proceedings until Preston went 6-0 up in the sixty fourth minute when Carter ran through from midfield and hit a low shot past Williams.
Parkin completed his hat trick, and the scoring, when he hit home a penalty after the referee had a spotted a foul in the U's penalty area with eighteen minutes remaining.
The final whistle went on a disappointing defeat and the U's would have been hurting as they trudged off to the changing room and work will be done as they return to league action next weekend.
U's: Williams, White (Thomas), Okuonghae, Reid, Tierney, Ifil, Fox, Wordsworth, Hackney (Izzet), Odejayi, Gillespie.
Subs: Cousins, Heath, Batth, Elito, Platt