Marcelo Bielsa admitted Leeds rode their luck as they narrowly beat West Brom 1-0 to overtake them at the top of the Sky Bet Championship.
Ezgjan Alioski scored the only goal, via a deflection off former Leeds defender Kyle Bartley.
Albion bossed the majority of the second half but could not find a way past a stubborn home defence.
Bielsa admitted: “It was big big effort from the team tonight.
“We tried to manage the match, but at the end West Brom’s creative play was difficult to defend.
“We put all our energy into defending which made it difficult to then put our energy into the attacks.”
And the Argentinian defended his decision, saying: “The change was not for his (Roberts) performance. He worked a lot but the shape of the match turned and changed.
“I was forced to make the change to put a more defensive player on the pitch.”
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