Old Trafford may have a more harmonious working environment in the absence of Roy Keane but controversy is never far away.

After Ruud van Nistelrooy's goal hoisted Manchester United to fourth place, Sven-Goran Eriksson was left wondering about the fitness of David Beckham, who was withdrawn from England's squad to face Portugal on Saturday after last night's game, and Paul Scholes, who was meant to be unfit for the Portugal game but played last night.

If Eriksson was dismayed to learn that Beckham has sustained a calf injury, the England coach must have been bewildered to see Scholes in the starting line-up.

Ferguson disclosed that Scholes was still being troubled by an ankle injury but the United manager did not offer any explanation for why Scholes was unavailable for England, nor an apology.

"He has not had much football and has been carrying an injury for a few weeks and we just have to be careful with him and how much we use him," Ferguson said. "He got through it. It [his ankle] was feeling very painful at the end but hopefully can get him fit next week for Bolton."

Eriksson is still entitled to ask some awkward questions of Ferguson after last night's game. He has already indicated that he may insist on Beckham joining the rest of his squad in Birmingham today, so his injury can be assessed by England's medical staff.

Scholes played the first 79 minutes of a prosaic victory that, though it raised United four places up the league, failed to dispel the fear that Keane's enforced absence for at least six weeks could have a seriously debilitating effect on Ferguson's team.

United's play was fragmented and directionless, with little width or penetration. Ferguson strode on to the pitch 20 minutes after the final whistle to remonstrate with his ground staff, apparently believing the pock-marked surface had contributed to their disjointed performance.

"I think we made it hard for ourselves," Ferguson said. "With all the possession we had, the control we had, we really should have finished the opponents off.

"We did create good openings but maybe tried to put too much icing on the cake, the extra pass, looking nice. We lacked the killer instinct."

Without Keane, Ferguson's side looked anything but invincible. In one interview at the weekend Keane described himself as "the robot, the mad man, the winner". For all his faults, though, last night showed how important he is for his club.

In Keane's absence Beckham took the captain's armband. Of more interest to the photographers was the fact that he was also wearing new boots - one bearing the name of Brooklyn, the other Romeo, his three-day-old son.

Yet Beckham's night was to end on a sorry note, when he limped off before the final whistle after a peripheral performance. "He's had a problem with his calf all week and it will keep him out of the England game," said Ferguson.

By then United's third successive home victory had been secured through Van Nistelrooy's 39th goal in his 50th appearance, although even that was shrouded in controversy.

At first it seemed as though Van Nistelrooy's usual accuracy had deserted him when, running on to Ryan Giggs's flick, he ballooned his shot over the bar but Mike Riley had noticed a slight tug from Ugo Ehiogu that would probably have been overlooked had the Dutchman not gone to ground.

As the protests raged, Van Nistelrooy finished emphatically from the penalty spot, while Ehiogu was left to reflect on the referee's generosity for brandishing only a yellow card when, as the last defender, he could easily have seen red.

"I think it was a very harsh penalty," said the Boro manager Steve McClaren. "To lose to something like that is very disappointing because apart from that we were hardly troubled."

It was, indeed, an unusually vapid performance from a United side that seldom threatened to extend their lead. It is inconceivable that Ferguson's players would have been so one-paced had Keane been around to spread his invective, urge on his colleagues and take the game by the scruff of its neck. Neither Nicky Butt nor Juan Sebastian Veron could dominate the centre of midfield and Giggs and Beckham flitted in and out.

Yet Middlesbrough failed to prey on their hosts' vulnerabilities and managed only two shots on target all night. Faced by a side playing well below their best, and with Keane conspicuous only by his absence, McClaren may reflect that they could have had something to show for their industry had they displayed a greater sense of adventure.