Champions League: Manchester United 0-1 Barcelona, 5 Talking Points

#4 United's defence tested, but how did they fare?

Smalling and Young endured a difficult 90 minutes, even against a below-par Barca attacking display

Playing against one of the world's best attacking tridents, which just happens to include Messi, was always going to be a tough ask for United's backline to contend with.

Collectively, they did well to shackle individual players for sustained periods and frustrate them too - but a slow start proved costly as Barcelona's increasing pressure finally told after well-worked moves through midfield early on.

Shaw, one of the club's best performers this season, was unfortunate to have an own goal chalked next to his name. He watched helplessly as Suarez's headed effort flicked off him on the way through, but the full-back defended well for the most part - especially to perfectly time a last-ditch recovery tackle on Sergi Roberto - which is much easier said than done. Especially when you've been booked after 20 minutes and will miss the return leg through suspension next week.

As for the centre-backs Smalling and Victor Lindelof, they had to constantly remain alert and were kept busy throughout.

Smalling was penalised for an overzealous nature when launching into tackles and also booked. His cynical yet no-nonsense approach would have been more beneficial if not playing against crafty opponents, who are aware of United's physical style in trying to frustrate Barca's playing style. His five fouls committed was a game-high and truthfully, he - just like Busquets - was lucky to stay on the pitch.

Ashley Young struggled to retain possession, his crossing was wildly inaccurate (3 of 11 successful) and endured a difficult night, while Diogo Dalot had an encouraging outing but was made to predominantly act as support for Shaw with an overlapping Semedo making himself a problem to defend against.