Manchester United must produce another unlikely Champions League comeback to keep their hopes alive after Barcelona left Old Trafford with a slender advantage following the quarter-final first leg.

Barcelona, with superstar Lionel Messi quiet by his standards, were nowhere near their best but secured the win after Luis Suarez's far post header from the Argentine's pass deflected in off Luke Shaw in the 12th minute and was confirmed by the video assistant referee after initially being given offside.

New Manchester United manager Ole Gunnar Solskjaer can take heart from his team's great endeavour but opportunities were at a premium, the best being a first-half header from Diego Dalot that he directed off target. In fact United did not muster a single shot on target.

Barcelona still posed a threat, with David de Gea saving from Philippe Coutinho and Messi - and United must now repeat their last-16 heroics against Paris St-Germain in France when they travel to the Nou Camp chasing a semi-final spot against Liverpool or Porto.