Tranmere Rovers have signed midfielders Lee O'Connor from Celtic and Josh Hawkes from Sunderland for undisclosed fees, on two-and-a-half year deals.
Republic of Ireland Under-21 international O'Connor, 21, has played 17 games for Rovers this season, having impressed on loan the previous season.
Hawkes, 22, scored one goal in 17 Rovers outings before his recall by the Wearsiders earlier this month.
The Teessider joined Sunderland from Hartlepool in September 2020.
"As soon as I heard Tranmere wanted to make it permanent, it was something I was keen to do," Hawkes said.
"It's really important for me at this stage of my career to be playing week in, week out.