United's second group game in this season's Central League Cup was away at Preston North End on Tuesday afternoon.
And the Lilywhites had a strong side out as they made use of the international break to give their first team, who were fresh from a 3-2 away defeat at QPR at the weekend, a full 90-minute run-out.
United fashioned the first opening of the day when Clough showed tenacity in midfield. He came away with possession, having tussled with Thomas, and he dropped a shoulder to make space. His effort from the edge of the area took a deflection and bobbled wide.
But it was the hosts who grabbed the lead when Smith was closed down quickly as he looked to clear. Barkhuizen got in the way, and he reacted first to get to the loose ball. The front man steadied himself before popping it into the net.
The lead was doubled when Barkhuizen pulled wide to take a pass from Thomas. He looked up and spotted Potts, who had made a late run. His volley from six-yards out was unstoppable.
More good work from Clough almost paid dividend when he showed a great touch before going past his marker. A thunderbolt was heading for the top corner until Rudd leaped high to tip it over.
It was a decent spell for the visitors and Mampala showed a clean pair of heels to O'Reilly before checking back to deliver from the left flank. It caught in the wind and Rudd had to palm it over as it threatened to creep beneath the bar.
Preston settled back into their stride and power from Potts took him to the byline. He fizzed a wicked delivery across the face of goal and Murphy was there to finish it off.
Two quickfire goals just before the break cemented the home advantage, with Potts there to double his tally for the day when Rafferty picked him out.
And Murphy also registered a brace when a long punt forward skimmed off Jack Ellis and into his path. He drew the stopper and bulged the net.
Things were much more even in the second period with the young United side working hard to make a mark.
But Smith had to be at his best on 54 minutes when Barkhuizen controlled a cross from Rafferty. Stood on the edge of the six-yard area he put his laces through it, only to see the agile stopper get his gloves to it and put it onto the bar.
Carlisle attacked in numbers with Abrahams dropping deep to get the ball. He fed it to Carr, and his deft touch sent Charters clear. A low rasping drive beat the keeper but also the upright.
Thomas grazed the bar with a thundering drive from distance at the other end, and Smith got both hands to a Murphy header as the game ebbed and flowed.
The home side won a penalty when Rodwell-Grant burst through to go one-on-one with Smith. The keeper clipped a heel and the whistle was blown.
The spot kick from Sinclair was saved, as was the follow-up from Rodwell-Grant, and Sinclair was thwarted a second time when he tried to sweep up the loose pieces.
United thought they'd registered on 75 minutes when Mampala shrugged off a challenge to angle into the box. Rudd was well beaten and relieved to see the fierce grasscutter smack into the post.
Carlisle pushed again and Mampala and Garvey exchanged passes as Leslie joined the forward play. He took over, and Rudd spread himself to make a vital block.
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Teams
Preston North End - Rudd, O'Reilly, Rafferty, Lindsay, Huntington, Thomas, Sinclair, Potts, Rodwell-Grant, Batkhuizen (c), Murphy. Subs - Hudson, Nevin, Baxter, Leigh, O'Neill.
Goals - Barkhuizen (7), Potts (13, 43), Murphy (34, 45)
Carlisle United - Smith, Barnett (Fishburn 46), Ellis (Watt 66), Kilsby, Leslie, Devine (c), Charters, Clough (Carr 60), Mampala, Abrahams (Garvey 78), Bell. Subs - Simons.
Booking - Watt (81)