Everton sit in the mix for European football as the season enters its final weeks, with Ndiaye one of the key figures in their push. That form has inevitably attracted interest from above, but Moyes was unequivocal when asked about the possibility of selling his standout attacker.
"He is the last person I would consider selling. There are others as well that I wouldn't want to sell, but my point is I have no interest in hearing the talk if there is talk out there."
He acknowledged the commercial reality that hangs over all clubs at every level.
"I don't think there is any club that is not a selling club at the right value for their player. I am not saying that means he is for sale, I am not, I just think it is a genuine thing where there is a price where people would say: 'well, we have to do something.'"
But Moyes placed the problem in a wider context, pointing to a cycle that has frustrated him throughout his career in management.
"It is getting too hard to build teams and also supporters are looking for a quick return which managers are not getting. So why would we be giving up their better players?"
He drew directly on his own history at the club.
"Maybe in years gone by when I had to sell Wayne Rooney, Jack Rodwell, Joleon Lescott and other ones at different times. I do want to change that but I think the club has to change that and the only way we do that is by becoming a bigger club where the players are coming in."
On Coleman, Moyes was warm but honest about the situation facing one of Everton's most decorated servants.
The Republic of Ireland captain, who turns 38 in October, has played just five times this season. He holds the club record for Premier League appearances with 372, and sits in a three-way tie for tenth on Everton's all-time appearance list on 433, alongside Leon Osman and Dixie Dean.
"I would make a place for him, one way or the other, whatever happened. There are no discussions at the moment, the focus is on the games."
He was candid about the state of those conversations.
"Obviously, we're working on things when we need to but if I'm honest, we've not really sat down and talked to Seamus. I talk to Seamus privately, and I'd like Seamus to stay at the club one way or another."
Moyes then explained in detail exactly what Coleman represents to Everton beyond his playing contribution.
"People could question him as a player, but I think he was elite level and what he's got in terms of the characteristics he brings to the football club, he's got a lot of Everton DNA in it. I think I need to retain that through the building, whether that's the academy, helping the young ones or even this morning when he was digging out the senior players, a couple of them for not running back or doing their work correctly."
"He's got a great idea of what the club requires. I have been away from the club, but I think he has been an ambassador for the club probably more than anybody."
"He was maybe one of the only people the supporters would believe and listen to, so I hope there is a role that we can make if it is not playing. Let's be fair he has had a brilliant career."
Moyes had one last line — delivered with a smile.
"One of the staff said the other day: 'Bloody hell gaffer, what did you pay sixty grand for him for?' I said: 'I know it was far too much!' We are happy to joke about with it."