While England coach Eddie Jones was furious with the incident, O'Connor said it was partly due the Tuilagi's frustration at the slow rehabilitation process from a series of injuries.
"I would be very surprised if it had further ramifications. Eddie is a smart guy," O'Connor told reporters.
"He was isolated off the back of being in rehab all time, and he wasn't enjoying all the things that he enjoys doing.
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"He understands that he made a mistake. He knows he got it wrong. He has come back with a renewed attitude. He understands what the standards are around the England environment."
Tuilagi, who has managed just one England appearance from the bench under Jones since the Australian took charge in 2015, has struggled with a groin issue, chest injuries and most recently a knee problem.
He was restricted to seven appearance for Leicester last season but O'Connor remains confident of the 26-year-old's ability to rediscover his form this season.
"He is doing really well. Injury-wise, he is flying, and in a lot better head-space. Hopefully, he will play against Bath in round one," O'Connor added. "He loves everything about the game. He is a pleasure to coach."
Leicester open their Premiership campaign against Bath on Sept. 3, while England are next in action when they host Argentina, Australia and Samoa at Twickenham in November.
(Reporting by Hardik Vyas in Bengaluru; Editing by John O'Brien)
