Chris Smalling is "just a tall guy with tall arms" as Jose Mourinho played down the Manchester United defender's clash with Barcelona superstar Lionel Messi in the Champions League.

Messi was left bruised and blooded in Barca's 1-0 first-leg quarter-final victory at Old Trafford after taking a blow on Wednesday.

The Barca captain – who was uncharacteristically quiet – was struck as Smalling attempted to win the ball ahead of the five-time Ballon d'Or winner midweek in Manchester.

"That situation with Smalling and Messi is nothing. It happens," former United manager Mourinho said during his appearance on RT.

"He's just a tall guy with tall arms. I don't think he has that intention. But they thought about him. And they have to think about him."

Mourinho added: "I don't know if they did or if it was Messi who decided to be quiet. I think a little bit of both. United were positively aggressive."

"By the defensive point of view, they [United] were good, keeping a lot of people behind the ball. But again, there are two legs, you will have to go away in the second game," Mourinho continued.

"If it was a group phase, where one point would be a positive result... They could, because Barcelona never killed the game."