The likely glory of another Premier League title is founded on austerity. Manchester United count at least as much on those who prevent goals as those who deliver them. Sir Alex Ferguson's side, with a five- point lead over Manchester City, are set to retain this trophy after a patient victory on the field where the championship was clinched last year.

United have had much better line-ups than this but on the domestic front there is know-how and self-belief. This is a side that is highly capable in the context of the Premier League. A point sufficed to clinch the title last season and United understand how to calibrate exactly the balance between risk and reward.

The sometimes gripping impulsiveness of days gone by is no longer a feature of United. They are still chastened by the losses they deserved when ousted from the Champions League by Basel, disappointment echoed by the manner in which Athletic Bilbao beat them with style and ease in the Europa League.

Those occasions raise questions that have yet to be addressed but answers are demanded of a Premier League that has Chelsea as its only force still active on the European scene. None of that will have entered United minds as a win was savoured. This was, above all, a demonstration of professionalism that slowly put Blackburn under strain.

It is no coincidence that United should have notched their goals inside the last 10 minutes. There was no frantic onslaught, just a gradual increase of pressure on Blackburn as they were pinned down. Misgivings arise over a goalkeeper when he is beaten from an acute angle but Antonio Valencia's drive for the opener after 81 minutes had accuracy and force.

The winger then suggested the strike had been as much cross as shot. It did not seem like that at the time but it is indisputable that he had caused the necessary havoc. A second goal, handsomely struck by the substitute Ashley Young, was an adornment to United's display but not one that seemed essential when the visitors, by then, had the occasion in its grip. With the five-point lead over City, a larger mastery seems imminent. Even so there can be no pretence that the world is agog at the football being produced in England. United, however, can postpone consideration of that fact as they anticipate another title.

It is a long time since United accepted that carefree, attacking football should be the priority. There was a period when that exuberance could be taken as a flaw when powerful opponents had a more cunning approach. These days United seldom forget to take care. The effectiveness testifies to the prowess of the group more than individual excellence.

Many a side would have felt doomed at the loss of Nemanja Vidic so early in the campaign. His season was ended through injury in the Champions League on the same night in December when Basel beat them 2-1. There has been little United could do to compensate properly for the removal of Vidic and Ferguson's line-up has had other moments when the test was too much for them.

Athletic Bilbao acted as if they could score at will when knocking United out of the Europa League on a 5-3 aggregate that understated the domination of the La Liga side. There was nothing that United could do on that occasion or in the Champions League, yet there was still resilience of a sort to sustain Ferguson's squad.

Jonny Evans, for instance, is making his mark at the core of the defence, even if he is not regarded as a true counterpart to Vidic. When not taking care in and around their penalty area, United certainly make time for sustaining the club's traditional commitment to attack. The tally of 76 goals in the League is notable, particularly since it is one ahead of City.

Wayne Rooney, finding the net regularly this season, has defined himself according to the needs of the side. In other periods, he has been more of a No10, a creative forward rather than a goal snatcher. He and his club repeatedly do what is specifically demanded by circumstances.

Defending of a specialised sort was also essential. The reservations about David de Gea, who looked a goalkeeper of intrinsic talent even during some turbulent occasions in his debut season with United, have disappeared with his acclimatisation to a new club and another version of football from what he was used to with Atlético Madrid.

He had given a terrible display against Blackburn on New Year's Eve, when the visitors won 3-2 at Old Trafford. De Gea was then dropped but he recovered soon enough. "He didn't let it get to him and is playing with confidence," Ferguson has said of the tribulations on the English scene.

At Ewood Park De Gea made the classic response of a goalkeeper who, in a potent side, typically has to settle for a sporadic role, denying Blackburn twice at the close of the first half. A man once in need of reassurance is now a comfort to United followers.