Scott McTominay continues to show promise for United, whose defence struggled to cope with Lionel Messi and Luis Suarez as well as the constant probings of Barcelona's midfield ball-players. 

Here's how Futaa rated the players after Barcelona's 1-0 win at Old Trafford.

Manchester United (4-3-3)

David de Gea Helpless for Barça’s goal and but saved acrobatically with his legs from Coutinho's drive. 7

Ashley Young Not his best game. Overhit crosses and constant fouls on Coutino. 5

Chris Smalling Physically imposing and stood up pretty well to the constant hassling from Luis Suarez, also gave Messi a souvenir blood nose from Old Trafford.  Executed a clear brief from his manager. 7

Victor Lindelöf Brought the ball well out of defence and looked assured and communicated well with fellow defenders. 6

Luke Shaw Struggled with Messi's trickery, understandably, was unlucky to deflect Suarez's into the net and picked up a booking that rules him out of the second leg. 6

Fred Recycled possession well with both feet and looked comfortable in the second half against a formidable midfield Barca unit. 6

Scott McTominay Didn't look out of his element at all. Rose to the occasion with a complete midfield display showing energy, good distribution and constructive aggression. 7

Paul Pogba Found Rashford with a brilliant through-ball but otherwise struggled to impose himself as we know he can. Took risks though and that's what fans love about Pogba. 6

Diogo Dalot Better going forward than back but missed a good chance to equalize with his head. The youngster is maturing fast, however, and must nail down a favoured position. Always slick and confident in possession. 6

Romelu Lukaku Worked hard up front but created very little for teammates. 5

Marcus Rashford Missed a brilliant chance in the second half and was withdrawn not looking 100% fit. Still, one of United's best players. 6

Barcelona (4-3-3)

Marc-André ter Stegen Untroubled in the first half but sometimes over-confident with his distribution in the second. 6

Nélson Semedo A constant threat going forward making overlapping runs and producing dangerous square balls. Slipped Suarez in with a cute ball only for the Uruguayan to lash it wide. 7

Gerard Piqué Outstanding display from the veteran centre back who made clearance after clearance when United's second-half pressure rained down. 8

Clément Lenglet Assured display from the Frenchman who's keeping compatriot and World Cup winner Samuel Umtiti out of the side. 7

Jordi Alba A threat going forward in the first half but rather less impressive in the second, not helped by his play-acting. 5

Ivan Rakitic Efficient in possession as always, and strode forward when the team needed his help to knit moves together. 7

Sergio Busquets Fouled McTominay early and was booked for pulling back Pogba. Continued to make fouls and didn't look himself. Still, managed to produce a delightful chipped ball to Messi in the buildup to the goal. Not a typical Busquets display.  

Arthur Melo Still only 22, the Brazilian is constantly improving and looks ridiculously comfortable recycling possession in the famous Tiki-Taka style. Grew quieter in the second period and was substituted.  6

Lionel Messi Dropped deep to make the play for the club that he captains. Showed a sublime touch to take Busquets' ball down and then clip a cross to Suárez for the decisive goal. Quiet but still effective, which is the measure of the man. 8

Luis Suárez The ex-Liverpool man was a constant menace and seemed to enjoy scoring a winner against an old rival at the Stretford End. 7

Philippe Coutinho Neat and tidy in possession and combined well with teammates in the first half, but was ineffective in the second. 5

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