While big things are expected of Mason Greenwood this season, Fletcher has told fans to watch out for Garner and believes he could be seen regularly over the course of the campaign.
“I think the history of the club says they demand and they want young players in the team and they support that," he told BBC Radio 5 Live.
“It does give your more time when you give youngsters a chance because people see it as refreshing and see it as building for the future.
“I think that they are more than ready to play, it's just that, can you have too many at once?
“People talk about the leaders and who is going to help them, which is an important side, so it's a difficult one but I'm sure as the season goes on you're going to see more of James Garner because he's top class.
“I'm surprised he's not featured so far but by the end of the season I'm sure that people will know who he is without a doubt, if you don't by now."