The 18-year-old, who can operate as a midfielder or as a wing-back, made his competitive debut for Leeds and came on as a substitute in the 73rd minute against Derby County on Saturday.
The youngster put in an assured performance and earned praise from his boss as Leeds thrashed their Championship rivals 4-1 at Pride Park.
Bielsa has made it clear that Shackleton will be starting against Bolton in the EFL Cup clash tomorrow.
Shackleton is a promising young talent but Bielsa has refused to predict what he will become in the future. The Argentine said that the Leeds midfielder has all the potential to become a successful player and that he has maturity beyond his years.
Bielsa also added that Shackleton is a dynamic player who loves to keep the game simple.
“One of the biggest attractions of this game is what we forecast many times does not happen,” said Bielsa, as quoted by Leeds Live.
“But having said that, I think Shackleton has many skills to be a successful player. The most important thing he has is a maturity which does not correspond to his age.”
“I saw a dynamic player. He makes choices that correspond to the skills he has. And that is very hard to achieve in football. Simple. He is a player who plays simple, he does many movements by surprise. He’s dynamic.”
Leeds have made a good start to their 2018-19 campaign, winning their opening two matches already.
Shackleton is a very promising young talent and he should improve under the tutelage of a world class manager like Bielsa. However, he needs to keep his focus on his game, and take every opportunity that comes on his way.