Cristiano Ronaldo continued his irrepressible goalscoring form with yet another delightful double to sink Portsmouth and send United back to the top of the Premier League.

His two goals – one a neat finish, the other a jaw-droppingly good 25-yard free-kick – came within three minutes of each other and completely deflated Harry Redknapp’s men.

What this excellent performance proves beyond doubt is just how ruthless the Reds can be. This was a game United controlled from start to finish, but it was less about blitzing a team for 90 minutes, and more about a clinical job, pitilessly carried out.

The visitors may have lost four key players to African Nations Cup duty, but they cannot really complain with new signings Lassana Diarra and Milan Baros bolstering their ranks. The simple fact is that United, on this attacking form, are unplayable for most opponents. Even for a Portsmouth side that has taken seven wins from 12 on the road this term - Redknapp's men arrived in Manchester confident, if perhaps quietly so.

For United it was a case of maintaining momentum. Unbeaten in 2008, the Reds’ chief aim was to regain top spot from Arsenal in what is turning into a see-saw claim for the title. Paul Scholes, making his 550th appearance for the Reds, was given his first start since mid-October, and the Salford-born midfield magician was heavily involved from the start, pinging passes all over the pitch.