The 20-time English champions hosted the Ligue 1 side in the first leg of their last-32 clash in the Europa League as Jose Mourinho’s side looked to secure a commanding aggregate lead ahead of the return trip to France.
And Zlatan Ibrahimovic made a 15th-minute breakthrough thanks to a deflected effort past the St Etienne goalkeeper with help from a deflection off Vincent Pajot.
However, Manchester United centre-half Bailly handed the visitors a chance to equalise after his sloppy back pass was intercepted only for Sergio Romero and the rest of the home side’s defence to smother the chance.
Indeed, Mourinho’s £30m summer signing struggled throughout the first half which led to criticism of the Manchester United defender during half-time from the club’s ex-striker Owen.
“Eric Bailly has been pretty poor this half – I must say. Saint-Etienne looked very dangerous,” said Owen.
“There was a mix-up at the start which was Bailly’s fault. Herrera was in control and out his arms out. Bailly under no pressure gives away a free-kick. He is getting walked past. A lot of the chances are coming from his left-hand side. They’re exploiting Bailly. He looks a bit sleepy.”
Ibrahimovic scored his second of the night after half-time before a late penalty sealed his hat-trick and a 3-0 win.
Bailly moved to Manchester United in a £30m deal from La Liga side Villarreal in the summer transfer window.
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