West Brom 4 Leeds United 1: Marcelo Bielsa explains Barry Douglas substitution

Douglas used Twitter to say sorry for what he called an “unprofessional” response to Bielsa’s surprising decision to replace him 17 minutes from the end of a game Leeds were losing 2-0.

The left-back’s show of dissent came as he made way for Jack Harrison, a switch which saw Gjanni Alioski drop into a defensive role and Harrison occupy the left wing.

Douglas had been one of United’s more consistent performers on a tough night that ended in a 4-1 defeat but Bielsa insisted he had been compelled to gamble by earlier strikes from Hal Robson-Kanu and Matt Phillips.

“Douglas had a regular performance,” Bielsa said. “He didn’t have problems against their number 10 (Phillips) but with the development of the game I thought I had to take a risky decision.

“I thought the pair of Alioski and Harrison would have a higher offensive impact than Douglas and Alioski. I thought that we’d reached the moment of the game where we had to take risks.”

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Douglas has been a dependable member of Bielsa’s line-up since a £3m move from West Brom’s local rivals Wolverhampton Wanderers in July, a club where he earned a Championship winners’ medal last season.

The Scot’s frustration was visible as he left the field but posting on Twitter in the hour after full-time, he said: “Wake up call that for every one of us but can’t dwell on it.

“I apologise for my reaction at being substituted, it was unprofessional of me, I was just disappointed at the score and emotions got the better of me. We will be back after the (international) break stronger.”

Bielsa was also asked about his decision to leave Samuel Saiz on the bench until the 78th minute, despite United’s pressing need for goals.

Leeds were 4-0 down within moments of Saiz taking to the field but his pass to Pablo Hernandez laid on a consolation goal in injury-time.

“With Saiz, I tried to give an interpretation of the offensive midfield position with a player who has different features and skills to Klich,” Bielsa said. “With Klich, his skills are mobility. With Saiz it’s creation.