Weary Newcastle picked up yet another win to further re-write the club's record books as they climbed up the table into sixth place.
Unlikely match winner Aaron Hughes, who settled the issue nine minutes into the second half to secure Newcastle's 800th top flight win at St James' Park and 1,400th at the ground in all competitions.
Southampton grabbed hold of midfield in the first half, but were completely overrun after the resumption as the outstanding Kieron Dyer, Jermaine Jenas, Hugo Viana and Gary Speed grabbed the game by the scuff of the neck with Viana setting up Hughes' winner.
Woeful defending saw Newcastle fall behind after just 70 seconds. From what was their own thrown-in, United lost possession and Brett Ormerod was released down the right and crossed for James Beattie to strike a 25-yard drive across Shay Given and in off the upright.
United were all over the place as the Saints stamped their authority in the centre of the park with Beattie ever dangerous as he led the line.
Steve Caldwell sliced a Beattie cross from the left inches over the bar and it was not until the 26th minute that United managed a shot of note when Viana fired just over from 25 yards.
Three minutes later Shola Ameobi cleverly turned Wayne Bridge only to see Antti Niemi claw out his shot from only eight yards.
That was the lift Newcastle wanted and they dominated the remainder of the first half.
An equaliser was always on the cards and it came four minutes from half time. Dyer was the architect when he raced on to Andy Griffin's pass, superbly turned Bridge before working his way up the byline and crossing for Ameobi to bundle in his third goal of the season.
Whatever Sir Boby Robson said at the break, certainly worked as they piled on the pressure and stormed in front after 54 minutes with a rare Hughes goal.
Viana's clinical pass with the outside of his left foot let in the Northern Ireland defender to finish with style, for his first goal since last season's FA Cup win at Peterborough.
Some of United's flowing football was breathtaking, but they could not find that all important third goal.
Dyer had a shot turned behind and Shearer was twice denied as he went in search of his 100th Newcastle Premiership goal. Niemi saved the first and then when he got a header on target, Matt Oakley popped up on the line to clear.
There was some nervous moments in the dying seconds especially when substitute Agustin Delgado turned to fire just over