Manchester United 3 Wigan Athletic 1: Ronaldo gives United a reason to relax

He was so relaxed yesterday that, with 20 minutes left to play, Sir Alex Ferguson turned his back for a few seconds to wave cheerily to his grandchildren in the back row of the directors' box. Old Trafford's grumpiest grandad was feeling extremely pleased with his decision to send on Cristiano Ronaldo at half-time, which proved the crucial move of the whole afternoon.

The 21-year-old scored with his first touch, he added his tenth of the season shortly afterwards and also showed he is capable of a more profound effect on this Manchester United team than can be expressed in goals and passes. The introduction of Ronaldo changed the mood in Old Trafford and when he was finally on the pitch he needed only two minutes to change the game.

It hardly needs stressing any more that Ronaldo has become United's pivotal figure this season but on days like these you can fully appreciate how far he has come from the puckish teenager to the driving force when goals are needed. Four goals in his last two games, his team top of the Premiership by four points, Ronaldo broke down the resistance of Wigan where an unusually clumsy Wayne Rooney had failed.

Before they lost to West Ham two weeks ago, United's players returned from their pre-match warm-up to watch Chelsea roar back and finish off Everton at the death. This time the news was much more palatable and the flaky draw that the champions were held to by Reading had left some of the players, Ferguson said, "elated". The United manager muttered about not getting "carried away" but his principal aim at the moment seems to be educating Jose Mourinho in the capricious nature of football. "Jose said last week we will drop points, but Jose doesn't realise he will drop points also," Ferguson said. "That's the nature of football - it happens. You hope you are consistent enough and don't drop too many."

In the long, inglorious history of Ferguson's taunting of opposition managers it was nothing more than a glancing blow but it will have registered with Mourinho none the less. Ferguson has been waiting for more than two years to discover how Mourinho reacts under pressure and his emphasis, of late, on discussing the fickle hand of fate seems designed to lay the seed of doubt with Chelsea.

"We didn't expect that [Chelsea to lose] but that's the nature of football. Look at the West Ham game: no one expected us to lose but we did," Ferguson said. "If we can maintain the consistency that we have shown then we will have a marvellous chance."

Ronaldo was on the bench with Louis Saha while Rio Ferdinand, Ryan Giggs and Gary Neville were rested, Ferguson's selection justified in his programme notes by his insistence that United's squad does have strength in depth.

"It's important that these players do feel they are part of it and making a contribution," he said. "When a big occasion comes and we need them, they have to have some minutes on the clock."

Paul Jewell did much the same; the injured Arjen de Zeeuw was missing and Josip Skoko and Denny Landzaat on the bench. With the match goalless at half-time, Wigan must have felt they had a chance of a point. Within 15 minutes of the restart they were three down and on their way to their fourth consecutive defeat that leaves them 14th with one win in eight games. Ronaldo nodded home the first direct from a Paul Scholes corner on 47 minutes.

Then he took the penalty after Gary Teale's blatant trip on Park Ji-Sung and, although Chris Kirkland guessed right to save it, the rebound dropped for Ronaldo to finish.

The question of whether United have a strong enough squad to outlast Chelsea appears to irk Ferguson. In the directors' box yesterday there was an impressive collection of rested players as well as the injured Michael Carrick and Alan Smith. It is when Ferguson talks up Kieran Richardson and John O'Shea, who both figured yesterday, that you wonder whether he is stretching his own credulity. The second string has already let him down against Southend and Copenhagen this season and one stroll against Wigan will not change that.

Darren Fletcher and Wes Brown were the most impressive and Ole Gunnar Solskjaer chipped in with the third on 59 minutes after Rooney had knocked down O'Shea's throughball to him. Leighton Baines scored Wigan's goal from a penalty given for Mikael Silvestre's foul on David Wright in injury time.

No side with as many points as United have now at the halfway point of the season have failed to go on to win the Premiership title. That's pressure, but it's nothing compared to the heat you feel in second place.

Goals: Ronaldo (47) 1-0; Ronaldo (pen, 50) 2-0; Solskjaer (59) 3-0; Baines 3-1 (pen, 90).

Manchester United (4-4-2): Van der Sar; Brown, Vidic, Silvestre, Evra (Heinze, 69); Fletcher (Ronaldo, h-t), Scholes (Richardson, 61), O'Shea, Park; Solskjaer, Rooney. Substitutes not used: Saha, Kuszczak (gk).

Wigan Athletic (4-1-4-1): Kirkland; Hall, Boyce, Jackson, Baines; Wright; Teale (Cotterill, 52), Johansson, Kilbane, Heskey; Todorov. Substitutes not used: Pollitt (gk), Landzaat, Cywka, Skoko.

Referee: M Riley (W Yorkshire).

Man of the match: Ronaldo.

Attendance: 76,018.