Leeds United head coach Marcelo Bielsa believes Samuel Saiz is one of the few members of his squad who can "make a difference by themselves."
The Whites boss, who was speaking ahead of Friday's Championship clash with Sheffield Wednesday, was quizzed over the impact of Adam Forshaw's return to the United squad following an ankle injury in pre-season.
Bielsa discussed his recovery by comparing Forshaw's capabilities with fellow midfielder Mateusz Klich and used playmaker Saiz as an example of someone who is irreplaceable in the United squad.
"Forshaw can play as Klich and Klich can play as Forshaw does," the Argentine replied.
"Klich is a complete player. He can play on each level of the pitch. He can defend and attack. He can play in the axis and can play on the side. Forshaw is the same kind of player, he is very dynamic and flexible.
"When he has to build offensive responses he's as important as when he has to build defensive ones. The physical performance is very important. They are not players who can make a difference by themselves.
"They make the difference by associating with their team-mates. They can't do what Samu Saiz does, I think the only player who can do what Samu Saiz can do is himself. They are all midfielders but Forshaw and Klich have different features to Saiz."
Forshaw has returned to the Whites match day squad in recent weeks after missing the start of the campaign and was a second half substitute at the weekend during the 2-1 defeat to Birmingham City.
Bielsa though revealed he was making good progress back towards full fitness: "Adam is a player ready to play. There is a difficulty he has to solve and this difficulty can only be solved by playing. Before getting injured he was the best player of the team."