Twelve months ago the Senegal international was without a squad number, banished from the first-team dressing room and playing for the under-23s after Koeman decided on the basis of a 45-minute pre-season friendly appearance he was not up to the task.
But with Everton’s failure to sign an adequate replacement for Romelu Lukaku in the summer Koeman was forced to eat humble pie and recall the striker, a £13.5million signing by Roberto Martinez in February 2016.
After scoring in the midweek Carabao Cup win over Sunderland, Niasse came off the bench on Saturday to score twice in the final 13 minutes and turn around a game heading the visitors’ way after Josh King’s goal early in the second half.
“It is not surprising to me because I know him,” said Koeman, who denied a story that Niasse had been refused a changing room locker last season.
“Last season was a totally different situation with Lukaku but we did not sign a striker and we have two strikers – Sandro (Ramirez) is 21, Dominic (Calvert-Lewis) is 20 – and that gave him a chance to be more close to the first team.
“The boy has that kind of quality and with his aggression and direct play he can create a lot of problems. No-one can stop him at the moment, he did well and all the credit is to the player.”