The Whites welcomed the Welsh side to Elland in the first match since suffering relegation from the Premier League last term, but were booed off the pitch by their own fans after a torrid first half.
Despite showing signs of promise from Crysencio Summerville, Daniel James and Wilfried Gnonto, it was Cardiff who took the lead through on-loan Nottingham Forest star Josh Bowler midway through the first half.
Things then got worse as former Chelsea academy graduate Ike Ugbo made it 2-0 after just 39 minutes, capitalising on some shambolic defending from Daniel Farke's side.
Any pre-match optimism drained away during that first half, with Cardiff's supporters relishing in their shock lead against the promotion favourites.
The second half got off to a great start for Leeds as club captain Liam Cooper headed home to claw one back, however he was immediately replaced by Charlie Cresswell after an awkward landing in another blow to the hosts.
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With plenty of work to do in the transfer market, Leeds will be desperately hoping to strengthen their side as they look to make an immediate return to the Premier League.
After suffering relegation in 2004, Leeds took 16 years to escape the EFL - something that they'll be keen to improve on this time around with a swift promotion.
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