AITOR KARANKA admits he was as surprised as anyone when George Friend was unable to train on the eve of Middlesbrough’s 1-0 defeat at Crystal Palace.

Karanka had included Friend in his planned line-up for the game at Selhurst Park, but was forced into a last-minute change of plan when his medical staff informed him the full-back would not be available for training on Friday.

With Calum Chambers and Antonio Barragan also unavailable because of injury, Karanka was forced to adopt a five-man backline to face Palace, with Boro suffering a 1-0 defeat courtesy of a first-half goal from Patrick van Aanholt.

The Boro head coach was clearly frustrated at the late disruption to his plans, and it is not the first time this season that Karanka has expressed surprise at the actions of his medical staff. He was also surprised to learn that Gaston Ramirez was unavailable for training at the end of last month.

Karanka said: “I had been training all week to play in a different shape, but when I went to the pitch yesterday, ten minutes after the training session (started), I knew that George wasn’t there.

“It was a surprise for me and I had to change everything because I didn’t know anything until the moment I arrived to the pitch ten minutes after the training session started. The only option I had was the shape that I had today.

“Yes (it was frustrating), because when you arrive every morning and you leave the training ground every night and you go to the pitch on the last day with everything under control - set pieces, the shape, the players who are going to play - and you have the surprise and you have Barragan and Calum Chambers injured and you don’t have another alternative it is frustrating.

“But we’ve played with the same shape in the first half and the second half and the game has been completely different so it’s not about the shape it’s about our game.”

Friend has suffered from a number of calf problems this season, but Karanka claims the defender’s latest problem is related to his knee and is unsure whether he will be available for next weekend’s trip to Stoke City.

He said: “I don’t know (how serious the problem is). I went to the pitch yesterday and the doctor told me that he couldn’t train because he had pain in his knee when I thought that the problem was in his calf.

“So I didn’t know anything and I don’t know anything. I don’t know if it’s a new injury or an injury he had in the past. But again it was a big surprise when I arrived at the pitch yesterday.”