O'Connell missed Ireland's summer tour of New Zealand with a knee injury and isn't being considered for Munster's fourth PRO12 fixture against the Dragons at Thomond Park.
And with the Heineken Cup opener against Racing Metro now just three weeks away and the autumn internationals not too far around the corner, Munster boss Rodd Penney admits he doesn't know when he'll be able to pick the veteran second row.
"He's making progress, which is great, but there's absolutely no deadline date for him to return," Penney told the Irish Independent.
"He's in a programme but there's no set guidelines on when he'll be back to play. If it takes a month it takes a month, two months then two months. It'll be what it'll be.
"It's probably a week-to-week thing. We've had a lot of discussions. When Paul feels like he's ready he'll be back on the grass.
"For me, to see the guy playing at the highest level at 100 per cent would be a wonderful thing, and being consistent in his ability to play at every level at 100 per cent, so the pragmatic view comes on the back of those things.
"It's very simple really - if you care for your players then those sorts of decisions about their welfare are no-brainers."
Munster wing Simon Zebo will feature for the first time this term this Saturday but fellow Ireland internationals Peter O'Mahony and Donnacha Ryan will have to wait at least another week before turning out for their province.