Rioli was starring in the round-five AFL win over North Melbourne when he suffered the high-grade tear and was helped from the MCG.
The original prognosis was at least seven weeks out and Clarkson said that had not changed.
Rioli is one of Hawthorn's most important players and they will be extremely cautious with his return, given they will want him fit for the finals.
"He won't play before the bye, I wouldn't think," Clarkson said on FoxSports.
"His progress from that in his rehab is going really well and we're pleased.
"But he's had hamstring injuries before and we want to make sure he gets it totally right."
Hawthorn, who have won their last eight games, have their bye in round 11.
Clarkson added the Hawks would probably play him more in attack once Rioli returns mid-season, rather than the speedster spending too much time in the midfield.
The Hawks also want to try Rioli in defence.
"We might just leave him (up) forward," Clarkson said.
"He's a really valuable player and we'd love to explore Cyril at halfback at different stages in his career, too.
"He's a centre-square specialist when he goes in for centre bounces and we'd love him to be around the ball more.
"We'll probably use him a fair bit in the front half, but from time to time he'll go in there, we'll see how it goes."
Meanwhile, Clarkson had no new information on Hawthorn's biggest off-field issue this year - the future of star key forward Lance Franklin.
The four-time All-Australian is out of contract at the end of the season and also is eligible for free agency.
Franklin has opted to put off contract negotiations until the season is over.
"He'll be in discussions with 'Bud' and 'Pickers' (manager Liam Pickering) over the course and they'll continue to touch base," Clarkson said.
"But really our attitude we've taken to it is he's contracted to us for 2013 and at some point in time the two parties will come together."
