The attacking midfielder joined on loan from Southampton in January.
The midfielder became the club’s second signing of the January transfer window, as he joined on loan from Southampton until the end of the season.
He has struggled to impress at the Saints since a £12million move from Bologna in the summer of 2012, having only managed six goals in the Premier League in that time.
And Karanka says that the player is keen to impress during this loan spell, insisting that the move to the Championship is not a step down for him.
“As a player, maybe not this year, but in the past everyone can see how good he is,” he told mfc.co.uk.
“He wants to play. It’s important for me and it’s not a problem that he hasn’t played the last year because he’s fully fit. He's training really hard because we have other important players and I know their character.”
“He’s a hungry player. You could think it’s a step back but for him it’s a step forward because he wants to keep going and keep improving his career.”
Karanka will now be hoping that Ramirez can play a part as Boro try to secure automatic promotion back to the Premier League.
They are currently second in the table, a point behind leaders Hull City and three ahead of Burnley in third, a position they would be keen to maintain or improve upon at the end of the season.
Their January signings could be a big part of that, potentially adding the extra boost the squad needs to ensure this season is a successful one.