However, Mowbray claimed "Marc is at the front of the queue as far as I'm concerned" when asked afterwards about his strikers.
The Celtic manager's faith was repaid against Hearts on Wednesday night when Fortune scored the clinching goal in a 2-0 win to take the Hoops to within eight points of Rangers at the top of the Clydesdale Bank Premier League table.
Fortune, now with nine goals under his belt ahead of the trip to Aberdeen on Saturday, said: "My confidence has always been the same.
"People told me what the manager had said in the media about me but my confidence was already high so that is just a bonus.
"He came here to build a strong team for Celtic and he will keep going the same way.
"It is a new team, there are some guys away, some have arrived, so it is different.
"There are a lot of new players but with work we can get better and better."
Former Celtic and Aberdeen striker Joe Miller believes the Hoops can claw back the deficit to win the title back from Rangers.
However, talking at Hampden yesterday where he was promoting ESPN's live coverage, he admitted the Dons are unlikely to finish much higher than their current sixth place.
"Mark McGhee has been chasing third spot and he will be looking for Hibs and Dundee United to slip up," he said.
"I don't know if it is a realistic target, I think a top-six position is but they have to keep plugging away and hope teams drop points.
"After a tough game against Raith Rovers they responded well against Hibs and showed there is a good spirit among the squad and Mark will be looking for them to continue that against Celtic."
Scottish Premier Winner 2009/10 Win Outright: Celtic 2/1