Wayne Rooney scored, but missed a penalty, on his return from knee injury as Manchester United beat West Ham United 1-0 in their FA Cup third round replay at Old Trafford.
Rooney, playing his first game since December 23, needed less than nine minutes to find the net, tapping in after good work from Anderson and Javier Hernandez.
However, he later skied the ball over from the penalty spot - his ninth such failure for Manchester United - as the home side endured a nervy second half to book a fourth round tie against Fulham.
The game's one real moment of quality came in the ninth minute, when it seemed like West Ham could get overrun.
Anderson, whose improved performances this season suggest he may finally be coming good as a United player, unleashed Hernandez with a glorious 40-yard through ball.
Hernandez, who looked fractionally offside, unselfishly squared for Rooney who slid the ball into the empty net.
Manchester United make a habit either of conceding the first goal and roaring back, or scoring first and slacking off.
Though they dominated play, they created few clear chances against a West Ham side missing key players Joe Cole, Kevin Nolan, Mark Noble and Matt Jarvis.
It was pragmatic stuff from West Ham boss Sam Allardyce, amid a run of four games in 11 games, but the visitors naturally lacked incisiveness in midfield.
Nani played for the first time in over two months, and the winger seemed intent on convincing Alex Ferguson he has a future at Old Trafford.
The Portuguese was unlucky to see a volley blocked by Dan Potts just before the half hour mark after he met a glorious cushioned lay-off from Antonio Valencia.
Rooney had the home team's next best chance just before the break, hitting a dipping 25-yarder that Jaaskelainen dived low to his right to push away.
The second period started with a bang, and an uncharacteristic miss by Hernandez. He adroitly robbed Alou Diarra who miscontrolled, but blazed his shot over from 10 yards.
At the other end, West Ham had a good penalty claim turned down after Rafael appeared to control with his forearm inside the box.
The visitors grew in confidence and Matt Taylor saw two chance go begging. First he tried to cross to Ricardo Vaz Te when he should have shot; then he blazed over following a Vaz Te backheel.
It should have been game over in the 79th minute when Jordan Spence handballed.
But Rooney sidefooted the ball into the crowd - there was no slip or loss of footing to blame the miss on. It was just a terrible penalty.
His record now stands at 17 scored from 26 penalties - Alex Ferguson has already called for Rooney to improve his conversion rate and this latest miss will not have amused him.
West Ham tired, and were unable to produce a late moment of magic - as Robin van Persie had in the first game - as a chilly night at Old Trafford produced a home win.
MAN OF THE MATCH
Ryan Giggs (Manchester United): Though his influence has waned, the 39-year-old produced a fine display of passing and even the odd burst of pace as he led United to victory.
Manchester United: Lindegaard 6, Rafael 7, Smalling 7, Jones 6, Buttner 6, Valencia 7, Anderson 7, Giggs 7, Nani 6, Hernandez 6, Rooney 6. Subs: Carrick 6, Scholes 6.
West Ham: Jaaskelainen 7, Spence 6, Tomkins 7, Reid 7, Potts 7; Diarra 5, O'Neill 5, Diame 6 Taylor 6, Vaz Te 6, C Cole 6. Subs: Collison 6, Nolan 6, Lee 6.