The 2008 Sandover Medallist was seen as a ready-made player to replace Jeff Farmer, but further surgery for a troublesome wrist has kept him sidelined since the 2008 NAB AFL Draft.
With Roger Hayden ruled out for up to eight weeks with a fractured fibula, Harvey said the No.21 draft pick should not be discounted at selection this week.
"Ballantyne might be a guy that we might look at," Harvey said from Fremantle Oval on Wednesday.
"He's had five months of running and training. Not football content, but five months of training."
Ballantyne, 21, booted 75 goals for Peel Thunder in the WAFL last year and Harvey said the lively forward wouldn't be fazed stepping up to the next level.
The coach said he was ready to play his first match last week, but a general bye in the WAFL held him back.
"We went through some match simulation with Ballantyne last Saturday because they didn't play (and) he was extraordinary in those results," Harvey said.
"He's a different type of player that I haven't seen in my time, with a little bit of the Farmer agility.
"We need a forward that can pressure a lot better than what we have had at the moment.
"He's not an 18-year-old, he's down the track a bit, so there's a bit more constitution about his body, and he's an interesting kid, nothing fazes him at all."
With Rhys Palmer (knee) and Ryan Crowley (foot) ruled out for the season and Chris Mayne, who is listed on the club's injury list as three weeks away, seemingly going backwards with his stress fracture, Fremantle is lacking injury cover.
"We knew when we went to the draft last year that if we had a run of injuries, and particularly long-term injuries, we were going to have problems," Harvey said.
"We haven't got that experience in the background; we haven't got that luxury.
"We're right into our first-year players; right on the level of not having any real experience to fall back on.
"That's why you never saw us putting too much expectation on our season pending those sorts of things."
