For three years O'Connell and Schmidt, the former Leinster coach, regularly locked horns in the GUINNESS PRO12.
But since 2013 they have been fighting as a united front with Ireland, and Schmidt is thrilled to have the 35-year-old with him rather than against him.
"The person I have come to know is exactly the person I thought he was from afar," Schmidt said.
"He has got incredible self-drive, an incredible intelligence about the game, about particular aspects of the game.
"He is incredibly driven to improve his own performance and thereby leads others in doing that. That is what I have learnt even more.
"I suppose that has been confirmed to me in the period of time that we have spent working together over the last 18 months when I first started looking a little more broadly when I knew I was going to take the position and then since been in situ."
Munster are currently third in the GUINNESS PRO12 table with five rounds of the regular season to go.
Interprovincial rivals Connacht are the next visitors to Thomond Park when action resumes at the end of the month.
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