Clark led the Demons' goal-kicking in his first season with the club last year, despite missing the last 10 games with the injury which is also expected to keep him out for the pre-season at least.
That means he won't get to combine with ex-Collingwood premiership forward Chris Dawes, who made his Demons debut in Friday night's pre-season games, until they have to do so under home and away pressure.
But Dawes said with 18-year-old Jesse Hogan proving himself an excellent fill-in on Friday night, Melbourne could at least rehearse their attacking structure.
"For Mitch it's about not being too eager to play round one and just dealing with his rehab properly," Dawes said.
"I keep saying to him `Don't get yourself up for round one just because it's round one, just make sure you do everything right.'
"I'm sure he's been hearing that from all the medical staff - play when you're ready, don't come back too early and risk further damage."
Hogan, an under-aged recruit who's not allowed to play in the season proper until next year, impressed greatly in Friday night's games against North Melbourne and Richmond, although the Demons lost both.
Dawes said Hogan already looked like a senior footballer but the year-long wait would benefit him long-term.
"I'm more focused on how good it's going to be in 12 months' time when we've got that man-child running around," Dawes said.
Dawes said the Demons also liked what they saw from young recruits Jack Viney, Jimmy Toumpas and Dean Kent and AFL-experienced newcomers David Rodan and Shannon Byrnes.
Dawes himself experienced some calf tightness and is expected to miss next Sunday's meeting with Port Adelaide in Renmark.