Swansea City Under-21s suffered a narrow defeat in their south Wales derby at the Joma High Performance Centre on Monday night.
Michael Reindorf put Cardiff ahead minutes shortly before half-time with a close-range finish, and it proved to be the only goal of the game.
Swansea had a handful of chances in a hard-fought contest through Ben Lloyd, Glory Nzingo and Kyrell Wilson, but the home side were unable to make them count.
In front of a large crowd the visitors made a bright start, with Arthur Parker and Iestyn Jones making important defensive interventions.
Parker was soon in action again, heading away a ball into the box after a quickly taken free-kick had caught out the Swans.
The hosts started to settle around 15 minutes in, and Sammy Henia-Kamau's ball found Govea down the left. The winger's ball was met by Mitchell Bates, but a covering defender was on hand to block the midfielder's effort.
Moments later, Jacob Cook saw his low-driven effort gathered by Jake Dennis in the Cardiff goal, before two more chances followed from corners as Richard Faakye's header was blocked at the near post, and Lloyd volleyed wide.
At the other end, Evan Watts was forced to get down quickly to deny Isaac Jefferies from close range, and then comfortably held a Cian Ashford free-kick.
But the Bluebirds did take the lead just before the break. In-form striker Reindorf tapped the ball home from a delivery by George.
The Swans had chances to level before the half-time whistle, but Cardiff defended stoutly to block strikes from Lloyd and Nzingo respectively.
Both sides exchanged chances in the early parts of the second period. Lloyd came closest, but scuffed the ball wide from the edge of the box.
Swansea went closer still when Nzingo's fine strike - which looked to be headed for the top corner - forced an acrobatic save from Dennis in the Cardiff goal.
Still Swansea pressed, Nzingo and Wilson getting into promising areas but finding themselves crowded out.
Reindorf came close to a second for the visitors following a run down the middle, but his final shot flew well over the bar.
The Bluebirds' striker came close again, this time his header forced another strong save from Watts in the Swansea goal.
Wilson then had a chance to loft the ball over Dennis, who had left his area to intercept, and the Cardiff keeper cynically handled outside the box to concede a free-kick.
The set-piece fell to Nzingo, but again the ball was cleared as the Swans were unable to find a leveller.
Swansea City Under-21s: Evan Watts, Arthur Parker, Sebastian Dabrowski, Jacob Cook (Morgan Bates 65), Richard Faakye, Iestyn Jones (Zac Jeanes 73), Glory Nzingo, Mitchell Bates (captain), Sammy Henia-Kamau (Kyrell Wilson 45), Ben Lloyd, Aimar Govea (Thomas Woodward 65).
Substitutes: Kit Margetson.