After a stuttering start to their Aviva Premiership campaign, the Tigers have decided to bolster their ranks with the arrival of utility back Afa Pakalani, along with front-rowers Kyle Traynor and Jake Kerr.
Tonga international Pakalani can play at wing or full-back, while Traynor is a recognised prop and Kerr features at hooker.
O'Connor has been pleased with the arrival of the trio and feels they all have bright future ahead of them at Welford Road.
"Afa is a good player in the back three. He has played his first Test rugby this year and is a good age profile for us. We've been looking for a bit of depth in our backline options.
"Kyle has plenty of experience with Edinburgh and Bristol as well as playing Test rugby, while Jake is an ambitious young man who had some success in Scotland age-groups."