The 19 year-old defender handled the cauldron of noise at Elland Road remarkably well, impressing in the middle of the back four alongside Michael Carrick even though he was perhaps more likely to break through at left-back.
"To be honest, young Zeki had a nightmare and missed virtually the whole of last season really," said Sir Alex. "He had really terrible tonsilitis and was out for over two months. He missed the FA Youth Cup final because of it.
"He's a natural left-back actually but the way we looked at it the other night was we didn't really have a back four you'd expect Manchester United to play.
"So we improvised with Antonio Valencia at right-back - he was phenomenal - and Carrick at centre-back as he's played there before, of course, and has got experience. Fabio was left-back and the gamble playing Fryers worked.
"He's lightning quick, the boy, absolutely greased lightning. He was terrific, not overawed and it was just a shame he got cramp at the end."