Danny Cowley has been appointed Portsmouth head coach on an initial deal until the end of the season.
The former Lincoln and Huddersfield boss has replaced Kenny Jackett on the south coast, with his brother Nicky also joining as his assistant.
Pompey have slid to 10th in the League One table after four straight defeats and host fellow play-off hopefuls Ipswich on Saturday.
“This is a club with unbelievable tradition, so the board didn’t need to sell it to us, we’re proud and privileged to be here,” said Danny Cowley on portsmouthfc.co.uk.
“Hopefully they saw two hard-working people who love the game and we’re delighted to be at Pompey.
“We always have the ambition of leaving a club in a better position than we found it. We’ll be doing everything in order to achieve that here.”
Jackett was sacked on March 14 after almost four years in charge at the Fratton Park club.
The 59-year-old paid the price for just one win in seven league games, and lost the delayed 2020 Papa John’s Trophy final to League Two side Salford.
“Having spent time with Danny and Nicky over the past few days – and speaking to those who know them well – I am delighted that we can finally announce their arrival at Fratton Park,” said Portsmouth chief executive Mark Catlin.
“We are all totally focused on giving Portsmouth Football Club the best chance of promotion in what is now, effectively, a 12-game mini-season.
“I would like to thank them both for the enthusiastic and professional way they have approached working with us for this period and there is an absolute collective desire to achieve success.”