Michael Carrick's first Champions League goal in three years gave Manchester United an unconvincing 1-0 victory over Galatasaray and a winning start to their Group H campaign at Old Trafford on Wednesday.
England midfielder Carrick finished a neat move by rounding keeper Fernando Muslera, keeping his balance and slotting home in the seventh minute.
But United could not build on their lead, and Galatasaray, appearing in the Champions League for the first time in six years, were unlucky not to leave with a point after hitting the woodwork three times through Nordin Amrabat, Hamit Altintop and Selcuk Inan.
Nani made United work harder for their win when Muslera saved the Portuguese winger's feeble 53rd-minute penalty following a foul on Brazilian defender Rafael.
Alex Ferguson's side failed to reach the Champions League knockout rounds last season - the first time since 2005-06 they had fallen at the group stage - and they won just one game at Old Trafford in two dismal European campaigns.
Subsequently Ferguson has made a point of challenging his players to eradicate their complacency and defensive vulnerability. Yet the players nearly embarrassed their manager after one minute.
Captain Nemanja Vidic was fortunate not to concede a penalty when he tripped Galatasaray's alert striker Umut Bulut and referee, Wolfgang Stark, waved play on.
It seemed the home side had shaken off early nerves when Carrick provided the breakthrough.
The midfielder exchanged two incisive passes with Robin van Persie and Shinji Kagawa before taking on Muslera in a one-on-one, but even though the keeper clipped Carrick's heels, he kept his composure as he lost his balance to slide in the finish.
The goal did little to deter the visitors, however, and United, sloppy in possession, could not exert control.
Instead, Galatasaray, working with a bold formation from coach Fatih Terim of two up front, forced United backwards, and twice before the break they were inches from an equaliser.
First Amrabat cut in from the left and bent a curling right-foot shot from 25 metres on to David de Gea's crossbar, and in the 39th minute Altintop, the former Bayern Munich midfielder, ripped a low shot on to the base of the post from the edge of the area.
Terim's side struck wood for the third time in the 56th minute, when Inan flicked a header on to the outside of Ge Gea's right-hand upright.
By then United's frustration had increased with Nani's penalty miss.
Right back Rafael won the penalty, drawing a foul from Burak Yilmaz as he burst into the area eight minutes after halftime. But the Portuguese stuttered in his runup and his weak spot-kick was easily saved by Muslera to his right.
Galatasaray came within millimetres of an equalizer again after 71 minutes.
The visitors broke quickly once a Nani penalty claim had been ignored, and after De Gea palmed away Yilmaz's shot to the edge of the area, the Spaniard brilliantly got his fingertips to substitute Emre Colak's fizzing follow-up effort.
Darren Fletcher, out for 10 months with a chronic bowel condition, came on as a substitute to make his first United appearance since their Champions League draw with Benfica at Old Trafford last November.
And Ferguson introduced Javier Hernandez and Danny Welbeck in search of a second goal, though even that would not have masked a mediocre performance from the 2011 finalists.