Roy Keane was given the warmest of welcomes, but nothing else on his return to his alma mater yesterday, his Sunderland team battling with impressive spirit and determination for 72 minutes, only to fall victim to the injury-plagued Louis Saha’s first Premier League goal since December.

United have suffered for the lack of a conventional centre-forward since opening day, but they have one now. The improvement Saha brought about after replacing Anderson at half-time was such that it called into question Sir Alex Ferguson’s decision not to start with the penetrative Frenchman.

As soon as he got on the pitch, Saha showed the attacking thrust and purpose the defending champions had lacked in a desultory first half, and he would have scored earlier with a tremendous solo effort, but for a notable save from Craig Gordon whose saves when United finally got out of second gear made him second only to Saha in the man-of-the-match ratings.

The winner was a classic centre-forward’s goal, headed in at the near post from Nani’s corner. Gordon’s maladroit part in it, coming to meet the corner and not getting there, was his only mistake.

The one was always going to be enough against opponents of limited ambition, who had come looking for a goalless stalemate.

For Sunderland it threatens to become a long, hard season. Defeat by Liverpool last weekend was not entirely unexpected, but a midweek thumping from Luton Town in the Carling Cup was a real shock to the system, and that opening day victory over Tottenham is but a distant memory now. Keane sought defensive security in a 4-5-1 formation, with his new signing from Southampton, Kenwyne Jones, ploughing a lone furrow up front and Michael Chopra pushing forward to join him from the right side of midfield. Jones was not Sunderland’s only newcomer. Danny Higginbotham, who was recruited from Stoke in midweek, was given his debut in central defence. The two new men worked their proverbial socks off, but have the look of Championship players elevated above their station.

For United, goals have been unusually scarce in the continuing absence of Cristiano Ronaldo, who was completing his suspension yesterday, and Wayne Rooney, who is itching to get back into action, but not quite ready.

Hence it was a puzzler, given the fact that Carlos Tevez is not an orthodox centre-forward, and needs the support of one, that Saha stayed rooted to the bench for so long.

Ferguson suggested afterwards that after a six-month lay-off Saha was not fit enough to last 90 minutes, but added: “He came through well, with no problems, and it’s a relief to have him back.”

Ferguson’s attacking options may have been limited of late but it was not always thus, of course, and there was an emotional reminder of yesteryear before kick-off, when the two teams formed a guard of honour for Ole-Gunnar Solskjaer, hero of United’s 1999 European Cup triumph, whose terrible catalogue of injuries finally forced him into premature retirement in midweek. Keane came down from his place in the stand to give his old comrade a bearhug.

The pleasantries over, Sunderland set about the unglamorous, but pardonable task of strangling the life out of the game. The onus was on United to break them down but, not for the first time this season, they struggled to do it. For their England contingent, at least it was good practice for Israel’s visit to Wembley in the Euro 2008 qualifiers next Saturday, when the opposition are expected to keep all 11 players behind the ball in search of a goalless draw.

The best chance of an instantly forgettable first half came just before the interval, when Nani squared a free kick to Paul Scholes, whose shot from 30 yards deflected off Danny Collins, leaving Gordon much relieved when it flew narrowly wide.

Sent on at the start of the second half, Saha immediately enlivened things with a crisp shot. He was flagged offside, but his intentions were both clear and welcome. Grateful to have a partner at last, Tevez quickly let fly from 25 yards. Gordon saved comfortably, but again the action came as a relief after the earlier torpor. The save was anything but comfortable after 56 minutes, when Rio Ferdinand played the ball up to Saha, who took it down on his chest and swivelled on the edge of the D before testing Gordon with a sweetly-executed volley.

After what had gone before, this was manna from heaven. Gordon was in the thick of it again midway through the second half, when he failed to hold Owen Hargreaves’ 25-yarder, but atoned by thwarting Scholes’s follow-up.

Scotland’s finest was finally undone when Saha, at the near post, beat him to Nani’s inswinging corner from the left to head in from three yards. Game over.

Ferguson said afterwards: “In the second half we brightened our game up, improved our play enormously and we deserved to win.” Spot on.

Keane’s verdict? “Of course we’d like to have tested their goalkeeper a bit more, but in defence of the players that’s easier said than done here. I’m pleased with their attitude, their effort and the performance. I’m more than confident that we’ll be fine come the end of the season.”

The matchwinner Saha said it was “a brilliant feeling” to be back. “The most important feeling is to win. I’m not looking only on my goal, the team performance was brilliant in the second half, it was very tough because Sunderland played a very organised game.”

Star man: Louis Saha (Manchester Utd)

Player ratings Manchester United: Van der Sar 6, Brown 6, Ferdinand 6, Vidic 6, Evra 6, Eagles 4 (Fletcher 66min), Hargreaves 6, Scholes 6, Nani 6 (O’Shea 84min), Anderson 6 (Saha ht, 8), Tevez 6.

Sunderland: Gordon 7, Nosworthy 7, McShane 6, Higginbotham 7, Collins 6, Leadbitter 6, Yorke 6, Etuhu 6 (Miller 82min), Wallace 6 (Stokes 82min), Chopra 5, Jones 6 (Murphy 69min)