Middlesbrough condemned hosts Manchester City to a third straight Premiership defeat, and a third league game without a goal.
City wasted a hatful of chances, including two glaring misses from substitute Robbie Fowler, as Boro clung on to a lead handed to them by City full-back Sun Jihai.
Boro have now gone five Premiership games without conceding a goal, although they rode their luck on several occasions.
"By our own admission, we didn't attack well today," said Boro boss Steve McClaren.
"You saw the character of the side who didn't play well, but had something to defend and defended magnificently." City boss Kevin Keegan was stunned by the result. He said: "I can't remember being involved in a game like that before.
"It was incredible. Our keeper Kevin Ellegaard didn't have a shot to save until the fifth minute of injury time, but Middlesbrough have gone away with the points. " City dominated the opening 30 minutes. Boro rarely ventured from outside their own half as the home side pressed at every opportunity.
In fact nobody in a red shirt had a shot on target throughout the whole of the 90 minutes and four minutes of stoppage time.
Shaun Wright-Phillips was especially dangerous. The diminutive midfielder caused the Boro defence all sorts of problems with some probing runs down the right flank.
But despite the youngsters best endeavours City could find no way through.
Paulo Wanchope headed straight at Boro keeper Mark Schwarzer, Trevor Sinclair had a shot palmed away and captain Sylvain Distin had a header cleared off the line.
Boro made the breakthrough on the half-hour mark. Juninho, scampering forward from midfield, picked out Gaizka Mendieta on the outside and the unfortunate Jihai turned in the Spaniards cross.
City had a penalty appeal waved away seven minutes from half time when Danny Mills, the Boro right-back, seemed to hold onto the shirt of Wanchope.
It was virtually one-way traffic after the break. Richard Dunne headed over, Schwarzer pushed aside a Wright-Phillips volley and Fowler, with only the keeper to beat on both occasions, failed to hit the target.
Boro should have had a second in the last minute of stoppage time, but Mendieta, after racing clear from inside his own half, was denied by Ellegaard.
The win lifts Middlesbrough into the top half of the Premiership, level on points with City.