Chelsea defender Kenneth Omeruo is the man in question, and he is set to tie up a loan deal until the end of the season.
The 20-year-old Nigeria international, who is yet to make his full debut for Chelsea, spent last season on loan at Dutch club ADO Den Haag.
When asked about Omeruo, Karanka said: "Kenneth I think so, I want him until the end of the season and I am happy because he is coming here to help and gives us more."
Karanka revealed earlier in the week the club were in talks with Chelsea and reports claim that Omeruo will not be the first debutant coming in from Stamford Bridge with Nathaniel Chalobah being suggested as next in.
But Karanka insists they are not just focusing on Chelsea and he even joked about Michael Essien.
"These Chelsea loans, it can become hard and I also saw Michael Essien and it seemed I was about to go to London and pick him up," he joked.
"Yes, we are working to take players but they need to be very good players as we have a good squad and we have to make sure they are better than they are here."
Talking about the defeat to Hull City, which saw Boro outplayed for the much of the game, he admitted he was disappointed as it ended a run of four games without defeat.
"We did not play with the same discipline, like we have," he said.
"We had chances to make it 1-1 but we conceded the second goal and the game was dead.
"I picked the players I could to win the game, I made five or six changes and we wanted to give people matches."