Manchester United earned early bragging rights over Manchester City by running out 2-0 winners during their pre-season friendly in Houston.Goals from Romelu Lukaku and Marcus Rashford within two minutes of each other gave Jose Mourinho victory over Pep Guardiola in front a crowd of 67,401 at the NRG Stadium.It was Lukaku who gave United the lead, latching onto Paul Pogba’s lofted pass.New City goalkeeper Ederson completely misjudged Pogba’s forward ball leaving Lukaku able to nod the ball past him. But the Belgian still had plenty of work to do from a tight angle with two City defenders running back towards the goal-line. However, he showed everyone exactly why he’s worth £75 million with a perfect finish.Just a few minutes later, the Red Devils were 2-0 up.Henrikh Mkhitaryan’s pass freed Rashford down the right - with makeshift left-back Fernandinho struggling - and the 19-year-old made no mistake with a fantastic strike.

But just because they won 2-0, it doesn’t mean all United players had the perfect night.

That’s because Chris Smalling was involved in a very embarrassing moment in the first half.

With the defender attempting to deal with an aerial through ball with Sergio Aguero lurking behind him, Smalling tried to head it back to David de Gea.

However, he only proceeded to stumble and fall over, making himself look extremely foolish.

Watch: Smalling embarrasses himself

Take a look:

And United fans weren’t particularly impressed with that incident and proceeded to criticise their own player on Twitter.

United fans react on Twitter

Check out the reaction:

Of course, with the arrival of Victor Lindelof for £31 million this summer, Smalling will find it very difficult to play regular first-team football at Old Trafford this season.

It’s believed a partnership of Lindelof and Eric Bailly - who Mourinho signed for £30 million last summer - will be the preferred pairing.

And Smalling certainly isn’t doing himself any favours by doing his best Phil Jones impression in pre-season friendlies.