The 27-year-old Tunisian was sent off in the Ibrox club's defeat by Derby County at Pride Park on Saturday after aiming a diving headbutt at the Scotland internationalist, Chris Martin, and will miss the Petrofac Training Cup first-round tie with Hibernian tonight, as well as the opening match of the SPFL Championship campaign at home to Hearts as a result of the SFA receiving a report on his misconduct from their English counterparts.
McCoist, who has revealed that Honduran midfielder Arnold Peralta is currently holed up in Paris due to visa problems, held a meeting with Mohsni on Sunday to address the occasional anger management issues which also sullied his career at Southend United. However, the Rangers manager has expressed a desire to keep the player and work on his clear psychological flaws despite the fact Baniyas Sports Club, based in Abu Dhabi, have already had two offers for him turned down this summer and remain interested.
"I don't think, at this time, we are in a position to get rid of players who will be big parts of our season unless there is an automatic replacement who is better," said McCoist. "I don't see that happening. We speak about the downside of Bilel, but him and Lee McCulloch scored in the region of 30 goals for us from centre-back.
"I had a good chat with [Mohsni] on Sunday. He knows it was totally unacceptable. He knows he was wrong. He let himself down and let his team-mates down. We can't have that from any of our players.
"I sat down with him and watched it again on Sunday and the boy has fouled him, but in no way, shape or form can you possibly react in the way that he did. It is a problem and one we are working to resolve."
Mohsni has now received three red cards since joining Rangers last season. He was punished for a bust-up with Gary Bollan, the Airdrieonians manager, after the final whistle of a league match last season and chastised by McCoist when he was ordered off for two bookable offences against Brechin City.
"I have said to him myself that, if I was the opposition manager, I would try to wind him up," said McCoist. "That is what he fell for at Airdrie. It is just a switch [that flicks] and it is something that he has had throughout his career."
Meanwhile, McCoist has revealed the reasons behind Peralta's failure to reappear for training at Murray Park following an extended break. The 25-year-old was ruled out of the World Cup finals for Honduras because of a thigh injury and was given additional time off to complete his recuperation.
McCoist insists the midfielder is now fit but is in Paris waiting for visa issues involving both himself and his girlfriend to be resolved. "The mystery that is Arnold Peralta is definitely coming back," McCoist added. "When he's coming back, I can't give you a definite on. He's been in Paris trying to sort a visa. If you're going to have problems, I'd suggest Paris is the place to have them."