The 27-year-old Senegal international striker reportedly stormed out of out of Palace’s offices.
“Meanwhile Oumar Niasse’s proposed £7 million move from Everton to Crystal Palace collapsed after demands from his representatives for a six-figure agents’ fee were rejected,” states the report in The Times.
“Niasse had travelled to Palace’s Beak Street office on deadline day and had a medical, but the transfer did not materialise.
“Everton refused to pay his representatives earlier in the day and it is understood Palace officials became increasingly exasperated during negotiations.
“Niasse, the Senegal striker, eventually stormed out of Palace’s offices and returned to Everton — where he will continue to be frozen out by Ronald Koeman, the manager.”
Niasse has been on the books of Everton since February 2016 when he joined from Russian club Lokomotiv Moscow for a transfer fee reported by BBC Sport to be worth £13.5 million.
The 27-year-old has struggled to make an impact at Goodison Park and spent the second half of last season on loan at Hull City.
The Senegalese striker scored four goals and provided one assist in 12 Premier League starts for Hull last season, as the Tigers got relegated to the Championship.
Everton have a strong squad, and Niasse is going to find it tough to get much playing time at Goodison Park this season.