Just a fortnight before the first Test against the All BlacksÂ in Christchurch, the Lions vice-captain admitted they had not been aggressive enough to compete with a Maori side brimming with passion and emotion.
"The Maori put more players into the ruck than we did and there are different refereeing interpretations at the ruck, but they were more aggressive than us at the breakdown, they were more aggressive than us all over the pitch," said O'Connell.
"Their aggression and their work at the breakdown was sharper than ours. That is a big lesson for us, a big wake-up call.
"There are lessons to be learned at the breakdown, line-out and scrum. There were a lot of good things in the line-out, but a lot of bad things as well.
"It is not like it was anything small for us today but we were beaten in a lot of areas - the line-out, the breakdown and overall aggression.
"I don't think that will happen again on this tour."