Leinster hope to have new signing Kane Douglas in camp and ready for action ahead of their European opener in October.
The Waratahs lock, who is currently playing in the National Rugby Championship for NSW Country, lifted the Super Rugby title earlier this year.
The 25-year-old, who has 14 Test caps, is yet to arrive in the Irish capital but O'Connor is confident that Douglas will be ready for the opening rounds of the Champions Cup.
Douglas is one of only three signings for the reigning Pro12 champions, along with centre Ben Te'o and Sean McCarthy.
"We've had a few positive conversations in relation to that and it will certainly be well in advance of that date," O'Connor told the Irish Times.
"We're just trying to work out the logistics of when that will actually be. There is a release process.
"We need to get him signed off by them. Nothing can happen until that's achieved.
"All things being equal, that's looking quite positive. It will be sooner rather than later".