Thirty-four players will now travel to South Africa for the three-Test Series in July.
O’Connor has graduated from the Welsh Exiles programme having previously been part of the Bath Academy.
He studied at Llandovery College and played for Scarlets U18 before playing for Wales U18 and was also capped at U20s level.
O’Connor began his rugby journey at Dorchester before being spotted by Dorset & Wilts for county matches and then moved into the Bath academy aged 15.
The 21-year-old gained experience in the English Championship last season with Nottingham and made his first competitive start for the Scarlets against the Ospreys on New Year’s Day this year.
