Marcelo Bielsa explains why Jamie Shackleton had to wait before making Leeds United a 'better side'

Nineteen-year-old Academy graduate Shackleton has had to be patient for opportunities in his breakthrough year but the teen was finally handed his first outing in nearly two months when replacing the injured Adam Forshaw in Saturday's Championship play-off semi-final first leg at Derby County.

Shackleton was introduced from the bench for Forshaw after 24 minutes in his natural centre midfield role and looks set to keep his place for Wednesday night's second leg at Elland Road with Forshaw still out with a hamstring injury.

The versatile Shackleton had previously been used as a right back by Bielsa who admits the teen has been somewhat stuck in the pecking order behind Forshaw, Matuesz Klich and former Chelsea loanee Lewis Baker in centre midfield and similarly with Luke Ayling, Gaetano Berardi and Stuart Dallas ahead of him at right back.

Bielsa also said the positive reaction of United's older players when Shackleton has been introduced into the side spoke volumes about his talents.

Bielsa said: "As a right back we had Ayling, Berardi and Dallas playing and as a no 8 we had Baker, Klich and Forshaw - they are players older than him and they have more experience than him.

"But every time he played, honestly, we saw him and there is a detail that is very important to me - how a player is accepted by his team mates.

"When the older players accept a new, young player it means that they like to have these players on their side.

"When a young player finds his space in a top team, in the natural competition you have for the positions, the one who comes in moves someone else out of the team.

"That's why from a team spirit, the only way you accept the arrival of a young player is when he makes the team better and for me this happened very clearly with Jamie Shackleton."