Despite Saturday's 2-0 Sky Bet Championship win at Brighton, Boro's hopes of making a late dash into the play-off spots look remote with just seven games left to play.
However, Karanka told the Evening Gazette: "This season is important until the last minute of the last game.
"It's important because we are representing the club and we need to respect the club, the league, the opposition and our supporters. The best way to do that is to play 100 per cent in every minute of every game.
"The supporters deserve all our respect, we are here for them, and the players need to show me that they want to be here next season.
"The person who thinks the league is finished is very, very wrong."