The 20-year old Australian U20 international is currently on loan from Hearts to Scottish First Division club Ayr United and Jefferies wishes he had him back at Tynecastle Stadium after seeing some impressive performances recently.
"The lad Ryan McGowan has been excellent at Ayr United and he will be in my thoughts for the start of the season," Jefferies told the club's official website.
"I have heard good reports about him, I watched him in training yesterday and I thought he looked decent.
"He was part of the Ryan Stevenson deal to stay there but maybe in hindsight given the injuries we've picked up I would have much preferred to have thought about bringing him in."
McGowan continues to train with Hearts three days a week whilst he is on loan at Somerset Park but he will not return to the playing field with the Premier League club until next season.