SOCCER:FROM ALEX Ferguson yesterday there was acclaim for Chris Smalling and the sense of a young man increasingly comfortable in his own skin, acclimatising to life as a Manchester United player and demonstrating the gifts that have elevated him from non-league football to the top tier of his profession in two-and-a-half years.

But there was one significant drawback as Ferguson contemplated the 159th Manchester derby at Old Trafford today and what threatens to be the most challenging assignment of Smalling’s career to date. It was that the 21-year-old was being discussed only because Rio Ferdinand’s injury problems have flared up again. The England captain is facing another fortnight out and, as Ferguson will be acutely aware, there is hard evidence that can have serious ramifications.

When you analyse the statistics it becomes clear how Ferdinand’s absence can rob United’s defence of its poise. With him in the side alongside Nemanja Vidic the team have conceded an average of 0.67 goals in their league games this season. When the pairing is broken up, it balloons to 1.4.

In short, United are more than twice as likely to concede when they are without their first-choice defensive partnership.

“They don’t always play together but, in the main games, it’s a fantastic partnership,” Ferguson noted. “They have the experience and quality behind them of going for championships.”

For United there are immediate dangers, particularly if Manchester City are emboldened to play with more ambition than they volunteered in the reverse fixture in November.

Smalling has started only three league matches and it has not been a flawless introduction, judging by the way he was sucked out of position in allowing Tuncay Sanli to cross for Stoke City’s goal at Old Trafford last month.

Smalling has never faced a striker as accomplished as Carlos Tevez when it comes to wearing down opponents and forcing his personality on to a game either, and, in essence, he is in the team only by default given Jonny Evans’ confidence issues.