AITOR KARANKA has revealed that Mustapha Carayol is still short of being able to complete 90 minutes for Middlesbrough.

Carayol will not be considered for tomorrow night’s trip to promotion rivals Derby County despite making a number of appearances for the club’s Under-21s.

It had been hoped the winger would be involved in the run-in more than he has been since returning to action, but Karanka does not think he is ready for the strains of a promotion fight just yet.

Karanka said: “I don't think he can play 90 minutes yet, maybe I am wrong and maybe he thinks that he can play.

“But in the intensity that we play ... he's been out for one year and with the games in the Under-21 I don't think he is ready to play in our intensity.

“I think it would be worse if I put him in the squad and on the pitch and he is not fit, it could be worse for him and worse for the team. We have to do the right thing and at the moment I think he is not ready to play with us.”

Karanka has not ruled out playing Carayol before the end of the season, though. The former Bristol Rovers man, who ruptured his cruciate knee ligament one year ago tomorrow, is out of contract in the summer, although Boro do have the option of a further year.

“The only problem Muzzy has now is that to put him in the squad I have to take one out,” said Karanka. “I have just 18 places and 18 players who were in the squad on Saturday worked very, very well so this is his biggest problem. He is a very good player but he has been out for one year.”

Middlesbrough head for Derby tomorrow looking for the three points that will lift them clear at the top of the Championship before travelling to Bournemouth this Saturday.

Defender Daniel Ayala hopes to have shrugged off a thigh problem sustained against Ipswich on Saturday. Full-back Ryan Fredericks remains sidelined with a hamstring problem.