Teenage striker Liam Soule scored Cardiff City’s winning goal in their Professional Under-23 Development League match against Bolton Wanderers at Cardiff Sports Campus.
Former West Brom youth player Soule, aged 18, scored the only goal two minutes after half-time.
City had Ben Margetson, the son of former Cardiff and Wales goalkeeper Martyn Margetson, sent off during the second half after being booked twice in eight minutes.
The Bluebirds included senior goalkeeper Brian Murphy, who made a series of excellent saves, while teenager Aaron Bolger was named Under-23 captain.
Bolger, a technically gifted box-to-box midfield player, joined Cardiff City on loan from Shamrock Rovers until the end of this season.
Murphy tipped a close range header over the bar after 18 minutes, while Tom Sang went close from a free-kick 30 yards out. His effort, though, was saved.
Cardiff went ahead two minutes into the second half thanks to Soule and then, just before the hour, Margetson put the ball past Bolton goalkeeper Matthew Alexander from a cross, but that was disallowed for offside.
That was Margetson’s final contribution because he was sent off soon after for a second bookable offence.
Tom Sang’s free-kick was saved by Alexander after 62 minutes, while Bolton started to press against 10-man City.
Murphy made a series of brilliant point-blank saves to keep his cleans sheet including a low, diving stop to his right from a fierce shot.
This is Cardiff’s first under-23 league win of the season and they now turn to next Monday’s trip to play Sheffield Wednesday (1pm). That is followed by an away game at Coventry City on Monday, September 23 (1pm).
The next home fixture for under-23 coach Andy Legg and his team is against Ipswich Town on Monday, October 14. That game will be at the Cardiff Sports Campus (1pm).
Cardiff City u-23: Brian Murphy, William Warnock, Jack Davies, Tristan Jones, Ben Margetson, Joel Bagan, Tom Sang, Tavio d’Almeida, Shamar Moore (Siya Ligendza 79), Aaron Bolger (capt), Liam Soule (Danny Williams 70). Subs not used: Sam Parsons, Warren Burwood (gk), Harry Pinchard.