Noel Whelan has questioned Marcelo Bielsa's decision to play Stuart Dallas at left-back for Leeds United at Blackburn Rovers when natural left-back Tom Pearce was available.
Pearce broke into the Leeds team towards the end of last season under former boss Paul Heckingbottom and the full-back caught the eye, attracting interest from Premier League clubs.
Leeds successfully fought off interest in Pearce and convinced him to put pen to paper to a new contract.
But he has struggled to win over Bielsa and in the absence of Barry Douglas, the Argentine put Dallas in at left-back at Ewood Park.
The winger struggled to cope and was exposed by Blackburn's Adam Armstrong, as Rovers won 2-1.
And Whelan has questioned playing Dallas when Pearce, an unused substitute, was available to be used.
"You've got players like Pearce. He's a natural left-back – should he have been in there?" Whelan said on BBC Radio Leeds.
"We talk about defending is an art and being a midfield player is an art, and a striker being an art.
"To throw someone in who doesn't know how to defend properly when someone [else] does and has been brought up with that defending technique, maybe Pearce was the right thing to do."
Pearce has played just twice for Leeds this season, in the EFL Cup.
