Cardiff win at The DenMillwall's U21 Development side narrowly lost out to their Cardiff City counterparts on a chilly afternoon at The Den.
The visitors began the better side and were in front with just two minutes on the clock; Joe Ralls opening up The Lions' backline with a superb through ball to Etien Velikonja who made no mistake in slotting past Tom Wellham in the Millwall goal.
The early goal gave Cardiff added impetus and they went close once more minutes later when Ralls' deflected free-kick had Wellham scampering across his line.
Ralls was at the heart of all of the visitors' best work and he came even closer to doubling their advantage when forcing Wellham into a save from close range following a well-worked move.
Thirty-seven minutes were on the clock before the hosts troubled City; Jack Sammoutis' teasing cross met by Fred Onyedinma but he couldn't get enough contact on his effort to test Elliot Parish.
Millwall improved as the second-half began and were unlucky to find themselves further behind when Rhys Healey's perfectly-weighted pass was turned home at the near post by the overlapping Luke Coulson.
Not to be deterred, The Lions pulled a goal back in eye-catching fashion when Onyedinma superbly controlled Josh Siafa's lofted ball forward before slotting calmly under Parish in the Cardiff goal.
They couldn't build on that, however, and Cardiff came away with a deserved victory.