Steve Cooper was sacked by Nottingham Forest on Tuesday amid reports the Premier League strugglers are set to hire Nuno Espirito Santo.
Cooper was axed after a dismal run of one win in 13 Premier League games left Forest just one place above the relegation zone.
The 44-year-old had been under fire throughout a dismal run of just one win in 13 league games, including five defeats from their last six matches.
Forest reportedly held talks with former Tottenham and Wolves boss Nuno about a return to the Premier League earlier on Tuesday.
"Steve Cooper has today been relieved of his duties as head coach of Nottingham Forest, following a spell of over two years in charge," a club statement said.
"The club will make a further announcement on the appointment of a new head coach in due course."
Cooper had retained the support of Forest fans after taking them from the bottom of the Championship to Premier League survival last season.
But with Cooper's summer of heavy investment in new signings failing to deliver the required results, Forest's Greek owner Evangelos Marinakis finally lost patience with the former Swansea boss.
"Everyone at Nottingham Forest would like to thank Steve for his superb contribution to our football club. His achievement in guiding Forest back to the Premier League will undoubtedly remain an iconic moment in the club's history," Marinakis said.
"We thank Steve for his dedication and commitment during his time with us, as well as the incredible connection he forged with our supporters and the city of Nottingham.
"Steve will always remain a friend of the Club and will forever be welcome at The City Ground. We wish him well in his future endeavours."
With Forest five points above the bottom three, reports suggest a deal for Nuno could be tied up before Saturday's crucial home match against Bournemouth.
Nuno has been out of work since leaving Saudi Pro League club Al-Ittihad in November.
Now the 49-year-old is in line for a return to the Premier League two years after his sacking from an ill-fated four-month spell at Tottenham.
He also had four years in charge of Wolves, guiding the club to promotion from the Championship in his first season in charge.
Wolves enjoyed consecutive seventh-place finishes in the Premier League and a run to the Europa League quarter-finals under Nuno's leadership.
Former Eintracht Frankfurt boss Oliver Glasner had also been linked with the Forest job before Nuno emerged as their top target.
