And having finally got some much-needed game time under his belt following surgery at the turn of the year, the 33-year-old was in good spirits and ready for more.
"I was definitely blowing but I'm delighted. I don't feel any ill-effects now or anything. I feel good," said O'Connell, who played 40 minutes at the University of Limerick.
"I'm injury free but I don't know about fit. It was very enjoyable.
"Luckily enough, it was a great day and a dry ball and that makes it harder on the lungs which is exactly what I needed. I've done plenty of fitness sessions which in some ways are harder than this.
"But it's just the intensity of getting up off the ground, of trying to be dynamic and get up and do it again five or six times in a row. That's something that's hard to replicate in training, especially in contact."
O'Connell now aims to be involved for the Munster senior side when they face Connacht the weekend after this, with another major landmark also on the horizon in the form of the Heineken Cup quarter-final at Harlequins on April 7.
"The hope would be to be involved in the next couple of RaboDirect PRO12 games, first and foremost," added O'Connell.
"The more games I can play the better. I think the Heineken Cup is definitely on for me. I'm available for selection anyway. The two lads (Donnacha Ryan and Donncha O'Callaghan) have been playing very well so we'll see what happens."
Munster boss Rob Penney was understandably delighted to see one of his stalwarts back in action, especially as the veteran second row has played just two games for his province so far this term.
Penney hinted that O'Connell may feature for his club side in the All Ireland League this weekend, with inclusion against Connacht on March 23 in Cork hopefully within his grasp.
"The next 48 hours will determine if he plays for his club this weekend. If it's the right thing for Paul, then it's the right thing," said Penney.
"We'll see how he backs up. I love the guys playing their club rugby when they can.
"I'm really pleased for him that he got through 40 minutes and looked vigorous. I was watching him closely around the contact area, the areas you need to be robust, and he could have been potentially compromised but he didn't look like he was flinching at any time.
"He looks like he is on the mend and he is on track for a little bit more footie in the next week or so."
O'Connell hasn't represented his country for close to a year, having missed the summer tour of New Zealand with a knee problem before sitting out all three autumn internationals and the current Championship campaign with a bulging disk.
He started the last six Tests for the Lions against the Springboks and All Blacks, though, and now has just under two months to persuade Warren Gatland that he is worthy of a place in his squad to travel to Hong Kong and Australia this summer.