The Teessiders head for Brighton on Saturday with their hopes of making a late surge into the Sky Bet Championship play-off positions looking forlorn after a run of 12 games which has brought just a single victory.
That has left Karanka's men sitting in 15th place in the table, 13 points adrift of the top six and facing a sixth consecutive season outside the top flight.
However, the Spaniard has no plans to tinker with either systems or personnel as he contemplates the final eight games of the campaign.
He told the Northern Echo: "I don't do experiments. I think experiments are for pre-season or not in the league.
"I prepare for every game 100 per cent. It's not the right place to experiment. I go to win the game, not experiment."