The poise and composure O'Connor showed at Newlands just three weeks after his nightmare against the All Blacks at Eden Park convinced Deans the 19-year-old is up to the pressures of starting a do-or-die Bledisloe Cup encounter.
"It was a remarkable response," Deans said.
"He's always had the talent but he's a young man so he's learning in the Test arena, which is very hard.
"Most young men get to learn the game at club level, where they can go back and seek the wise counsel of some elders, and the support and confidence.
"Whereas James is playing his learning experience in a Test match where he's got millions watching. The scrutiny is enormous, the consequence of error is often enormous, so it's tough.
"But he's shown the sort of courage he's got and the capability ... he wouldn't see it as intense pressure; he wants to be out there and he's shown on the weekend that he's more than ready."