Real Madrid manager Jose Mourinho has thrown down the gauntlet to his players, warning them that no one should feel their place in the side is assured.
Goalkeeper Iker Casillas was dropped for Real's 3-2 loss to Malaga last month, reflecting the tough love attitude Mourinho has implemented in response to his side's dismal season so far.
The Spanish champions host Real Sociedad on Sunday in their first match of 2013 and Mourinho has refused to reveal whether Casillas will return to the starting line-up.
"The players know who will play in goal," he said. "All I will say is that whoever plays tomorrow will not play in the Copa del Rey on Wednesday.
"Confidence often translates into performances, but it is just as important to be competitive and find a balance in every position. Being in a permanent comfort zone is not good for the players."
Mourinho believes the axing of Casillas should send a warning to Real's stars that complacency will be punished as Los Blancos attempt to bridge the 16-point gap to leaders Barcelona.
"We are going to play like we're league leaders," he said. "We have to think about ourselves, game by game.
"There is always room for improvement - I dislike living in a comfort zone. I am never comfortable, ever, much less when we fail to get the results we want."
Argentine legend Diego Maradona backed Mourinho's decision to drop Casillas, insisting it encourages the players to fight for their position.