first-half goal from Wayne Rooney gave Manchester United a 1-0 win over promoted Birmingham in their opening Premier League fixture of the season at Old Trafford.
The England striker finished from close range after his header rebounded off the post on 34 minutes.
United dominated possession but were unable to take their chances while, in the same passage of play with 19 minutes remaining, Dimitar Berbatov had a header cleared off the line by Lee Carsley and a cast-iron penalty turned down after Steven Carr trod on his foot.
But it was not all plain sailing for the hosts, as their makeshift defence looked shaky in the absence of injured duo Nemanja Vidic and Rio Ferdinand - the latter ruled out minutes before kick-off with a calf injury picked up in training.
After falling behind Birmingham had their chances to level, with Patrice Evra clearing Franck Queudrue's header off the line and Ben Foster saving well from substitute Cristian Benitez when the Ecuador striker raced clear of the United defence.
United could and should have extended their lead though as, in addition to a poor miss from Darren Fletcher and Berbatov's bad luck, Rooney flicked a header inches wide and had two long-range shots well-saved by Joe Hart while substitute Michael Owen should have marked his Premier League debut for United with an injury-time goal but he was denied by Hart.
Despite losing Cristiano Ronaldo to Real Madrid, United's teamwork and attacking intent was exceptional with Ronaldo's replacement Antonio Valencia a willing runner and ready to play the early ball when his pace freed him out wide.
Nani also impressed before coming off after suffering a reaction to the dislocated shoulder he picked up in the Community Shield defeat to Chelsea.
United had chance after chance as they bombarded Birmingham with free-flowing attacks from both flanks. Fletcher and Paul Scholes worked to contain a packed Blues midfield and slipped the ball wide as often as possible.
Carr was fortunate not to be dismissed on nine minutes when he brought Berbatov down on the edge of the box after Joe Hart's poor clearance was quickly threaded to the Bulgarian by Valencia.
From the subsequent counter-attack James McFadden put a curling effort wide after he cut inside from the left to leave the otherwise impressive Fabio stranded.
The young Brazilian covered admirably at right-back for his injured twin Rafael, bombing down the win in identical fashion to his brother and working well with Valencia.
Rooney, meanwhile, was relishing his central attacking role and forced an excellent save from Hart with a dipping, 25-yard shot on 12 minutes.
Fabio showed his Cafu-esque attacking ability just after the half hour with a bounding run down the right that culminated in a low drive that Hart did well to parry.
United took the lead soon afterwards with a clinical counter attack started by John O'Shea's long ball.
Rooney flicked it on to Berbatov, who casually nodded the ball down to Nani on the left whose cross was flicked off the far post by Rooney, who had continued his run and was perfectly placed to knock the loose ball past the helpless Hart.
Birmingham were on the rack but they were organised and bright on the counter. They could have levelled four minutes after United went ahead but Queudrue, unmarked, met Sebastian Larsson's excellent corner with a powerful header that Evra was well-positioned to clear.
Fletcher had his injury-time horror miss and United went into the break a goal to the good.
Nani was replaced by Ryan Giggs at half-time but United's stride was not broken in the slightest as they came out hungry for a second.
Rooney forced another good stop by on-loan Manchester City keeper Hart with a chest down and half-volley, while Berbatov was denied an obvious goal-scoring opportunity when Queudrue flew across to nick Rooney's perfectly-weighted centre away as the Bulgarian striker waited to complete a simple headed finish.
And so it continued. Camerone Jerome deflected a Giggs free-kick just over the bar, Berbatov thought he had scored when he headed Fabio's deep cross to the top right but Carsley was on hand to clear off the line, Paul Scholes had a low drive deflected just wide after good interplay between Rooney, Owen and Valencia while Rooney looked on in agony as his flicked header from Giggs's precision cross bounced just the wrong side of the far post.
Birmingham had two key chances to level, though, with their attacks rare but relatively incisive, showing boss Alex McLeish that they could have some impact this season.
Midfielder Keith Fahey drilled a low shot inches wide with Foster beaten while, with 12 minutes remaining, the pace of Benitez took him away from United's defence before Foster made a smart stop to deny him a dream start in England.
Owen, signed on a free from Newcastle, looked bright after he came on for the last quarter hour and showed a superb turn of pace to race clear of the Birmingham defence in the 92nd minute.
Unfortunately for the former Liverpool and Real Madrid star, his finish was too straight and Hart made himself big to block for a corner.
It was not to be a fairytale start for Owen but United sealed the win to start their title defence in solid fashion while Birmingham, despite defeat, will take heart after looking competitive against the champions.