The Bluebirds won their opening 2025/26 Vertu Trophy fixture, with Callum Robinson scoring the only goal against Exeter City on Tuesday night.
City's starting XI combined youth and experience with first opportunities given to Gabriel Osho and Omari Kellyman, while Academy graduates Luey Giles, Dakarai Mafico and Tanatswa Nyakuhwa were also given starts.
It was Giles who went close early on. The left-back struck across goal with his weaker foot, but opposition goalkeeper Jack Bycroft made a good save.
The home side went up the other end and had two quick chances of their own. Matt Turner made a good stop to deny Reece Cole, while Perry Ng showed his defensive brilliance four minutes later to clear off the line.
Exeter City's best chance of the opening half came 27 minutes in when young forward Kieran Wilson broke in behind, but he failed to test Turner in a one-on-one situation.
Another Bluebirds bow came 35 minutes in as U21 player Troy Perrett replaced Kellyman.
City almost netted the opener deep into first half injury time, but Callum Robinson's low strike was kept out.
It was that man who did find the breakthrough early in the second half though, with Cal getting his opening goal of the season.
Substitute Cian Ashford's dangerous cross evaded the defence, but not Robinson, who found the net with a header off the underside of the bar.
City almost added a second goal moments after the hour mark, but the impressive David Turnbull saw his powerful effort drift just off target.
It was an end-to-end finish to the game, with Exeter City looking to force a penalty shootout and a potential two group points, while City looked to secure their win.
Ashford was shown a second yellow card in added time, while the hosts saw a goal ruled out. Jack Fitzwater headed home, but the flag was already up.
The hosts kept up the late pressure, with goalkeeper Bycroft even going up for a corner, but it was Brian Barry-Murphy's side who held on to get their first three points in the group.
FINAL SCORE: EXETER CITY 0-1 CARDIFF CITY
Exeter City: Bycroft, Oakes, Sweeney, Fitzwater, Yfeko (Woodhouse 59'), Andrew (Rydel 59'), Francis, McMillan (Cox 74'), Cole (Brierley 46'), Wareham, Wilson (Oluwabori 74'). Subs Not Used: Whitworth, Cummins.
Cardiff City: Turner, Ng, Lawlor (Fish 46'), Osho (Kpakio 72'), Giles, Mafico, Turnbull, Kellyman (Perrett 35'), Nyakuhwa, Davies (Ashford 46'), Robinson (Willock 77'). Subs Not Used: Higgs, Wintle.