Rioli is inching closer to a comeback from a hamstring tendon injury suffered in round 15.
A preliminary final in two weeks looks to be his earliest opportunity, but first the Hawks must step up Rioli's training.
"He's going quite well. He's obviously not available to play this week and we'll just continue to track his progress over the course of the next week or so," Clarkson said on Thursday.
"At some point in time we're going to have to step up his program and when you step up that program you run the risk of a breakdown.
"Or he responds really well to it and he can cope with the extra demands that you place on him.
"So that will happen over the course of the next week to 10 days.
"You've got to take every risk in that regard and anyone coming back from a soft-tissue injury - Sydney is going through exactly the same thing with Josh Kennedy and Benny McGlynn over the last week or so to determine their availability.
"So it's always a risk when you've got guys coming back from a soft tissue."
Hamstring issues have restricted Rioli to just 11 games this year and he won't have played for 12 weeks by preliminary final weekend.
Clarkson said the 25-year-old remains in good spirits as his teammates embark on their finals campaign without him, starting with Geelong in a qualifying final this Friday night.
"I don't think it's tough on him all that much because he knows if he does get through there's the opportunity to play in a preliminary final," he said.
"If he does get through he's got that dangling carrot so we'll wait and see how he goes."
