Portsmouth have sacked head coach Danny Cowley after a run of nine League One games without a win left them nine points from the play-off places.
His brother – and assistant – Nicky has also been sacked, with the pair spending 22 months at Fratton Park.
The former Lincoln and Huddersfield coaches had replaced Kenny Jackett.
They led Pompey to an eighth-placed finish in 2020-21 – missing out on the play-offs by two points – before guiding them to 10th last season.
“We are desperately disappointed that, following our recent run of results, we have today made the difficult decision to part company with Danny and Nicky,” said chief executive Andrew Cullen.
“Both Danny and Nicky have given everything to Pompey, working so hard inside and outside of the training ground with a determination to bring success – not just to the football club, but to the city of Portsmouth and the wider community.”
In the 97 matches Cowley and his brother were in charge for, Portsmouth won 42 times and lost 28 games in all competitions.
With the club having reached the play-off semi-finals in the two campaigns prior to their appointment, the pressure was on to make the top six and push Pompey back towards the second tier after 11 years away.
But having missed out on a top-six finish for the next two seasons and winning just once in their past 14 League One games – a 1-0 win at Forest Green Rovers on 22 October – Portsmouth’s ownership have decided to act with the club in 12th place.
“We must now look forward and with 24 league games still to play, we will focus all our efforts towards delivering the targets we set for this season,” Cullen told the club website.
“The search for a new coaching team will commence immediately.”
More to follow.