Watford's woeful season took another turn for the worse as they conceded four first-half goals in a 5-1 defeat at Cardiff to drop into the Championship relegation zone.
Rising Republic of Ireland star Jack Moylan scored twice in the first half, winning and converting an 11th-minute penalty and then picking his spot to beat Federico Ravaglia in a one-on one in the 35th.
Hornets skipper Mattie Pollock had brought down Moylan for the penalty and then headed into his own net from a corner in the 41st minute before Ollie Tanner added the fourth in the fifth minute of first-half added time.
Having lost to bottom of the table Burnley 4-0 at home last weekend, with all the goals coming in the first half, it was another slap in the face for the 500 travelling Hornets fans who once again expressed their discontent with the owners and the manager.
Alessio Dionisi signed a two-year deal to manage Watford in June when he became their 12th manager, excluding interim appointments, to take charge of the club since the end of the 2020-21 season under Gino Pozzo's ownership.
This was a fourth defeat in a row and the sixth in the last seven games. With Burnley continuing their revival with a draw at home against Charlton it meant Dionisi's side slipped to 22nd in the table while the Bluebirds flew up to 18th.
Last weekend the Watford faithful started chanting "Sack the board" at Vicarage Road and there were boos all round for the manager and his players at the end of their latest humiliation.
For Cardiff it was only their second win of the season and it could have been by even more goals, though Watford had the first clear-cut chance of the game when Myron Boadu ran onto a poor back-pass by Dylan Lawlor but failed to beat Nathan Trott in the home goal.
Moylan's brace turned the game in favour of Cardiff, who were ruthless throughout.
After their dominant first half, Chris Willock won a second penalty in the 64th minute and - with Moylan still on the pitch and on a hat-trick - picked himself up and saw his spot-kick saved by Ravaglia.
The Watford keeper could not stop substitute Callum Robinson from adding a fifth goal in the 85th minute.
Hector Kyprianou headed home a consolation goal two minutes later, although not even that could stop the boos at the final whistle from the Watford fans.
The managers
Cardiff City head coach Brian Barry-Murphy:
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Watford head coach Alessio Dionisi:
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