Dan Harding's first half goal proved decisive as Saints earned a vital 1-0 win over promotion chasing Leeds United.

A strong performance from start to finish saw Alan Pardew's side edge out the Whites to avenge a defeat by the same scoreline at Elland Road back in December.

Saints got their goal during a period of ascendancy in the first half through one of the more unlikely sources as Harding popped up against his former club to finish a move from close range and earn the hosts a vital win at St. Mary's.

Saints: Davis, Otsemobor (Thomas 15), Fonte, Jaidi, Harding, Puncheon, Hammond, Schneiderlin, Lallana, Lambert, Barnard (Papa Waigo 71). Subs (not used): Bialkowski, Seaborne, Wotton, Oxlade-Chamberlain, Connolly.

Leeds: Ankergren, White (Bromby 46), Naylor, Kisnorbo, Hughes, Howson, Snodgrass, Doyle, McSheffrey (Kilkenny 61), Beckford, Becchio (Gradel 76). Subs (not used): Martin, Crowe, Johnson, Bromby, Dickov.

Referee: Mr. P. Walton (Northants)

Attendance: 30,794 (including 2,336 away)

The starting lined up remained unchanged from recent games, with David Connolly making his first appearance in the squad since the turn of the year, taking his place amongst the substitutes.

Saints got things under way attacking the Northam End on a bright south coast day. The match lived up to its early billing as being a competitive encounter with an openness from both teams going forward added to by the atmosphere from the capacity crowd inside the stadium.

In the fourth minute, the hosts produced a fine early move which arrived shortly after Rickie Lambert had headed narrowly wide from Dean Hammond's cross, and Adam Lallana was at the heart of it. The youngster collected the ball on the left and started a run which was intercepted, but the ball found its way to Hammond. The skipper played the attacking midfielder back into the penalty area where Lallana laid the ball on to Puncheon, but the former MK Dons man clipped his shot wide of Ankergren's goal.

The visitors responded with a dangerous looking free-kick from Gary McSheffrey, but the forward's effort struck Luciano Becchio en route to goal and stayed out.

At the other end, Jon Otsemobor launched a long free-kick into the area which Radhi Jaidi powerfully met, but saw his header fly over the crossbar.

Leeds remained a threat on the counter-attack with Jermaine Beckford testing the water with a shot from distance before McSheffrey's menacing run set Becchio through, but the Argentine's touch let him down when well placed inside the area.

On the quarter hour mark, Otsemobor had to be replaced after picking up a knock and he was replaced by Wayne Thomas who slotted in at right back.

Hammond warmed Ankergren's hands with a shot on the edge of the area before knocking a further effort from 18 yards narrowly over the top just a few moments later.

Saints continued to apply the pressure moving forward, and Puncheon almost gave Alan Pardew's side the lead on 19 minutes when he struck the base of the post with a firm shot after cutting in from the left hand side.

On 25 the momentum paid off as Saints took the lead. Rickie Lambert collected the ball at the far post and held it up for Puncheon who picked out ex Whites defender Dan Harding and he was on hand to pass the ball into the net from three yards out.

Lee Barnard went close with a drive from just inside the box which came off the head of Kisnorbo and from a second corner on the back of that attack, Saints thought they had doubled their advantage when Jaidi stabbed home from close range but referee Peter Walton chalked it off for a foul.

A second for the hosts remained on the cards as the visitors scrapped to keep the ball out on 35 with both Morgan Scheniderlin and Barnard somehow kept out on the goal line.

Inside the last five minutes of the half the match became more fraught as a series of infringements seemed to go unnoticed, the pick of which being Barnard hauled down just outside of the area when clean through on goal.

Whites midfielder Jon Howson was booked however, for a trip on Lallana as the half came to a close.

Half Time: Saints 1-0 Leeds

The fast paced nature of the new half saw the game take a while to settle down as a result but when it did, Saints continued to be comfortable on the ball as they stretched their opponents on numerous occasions in the final third.

The bandaged headed defender Kisnorbo was booked for a foul on Lambert which provided an opportunity for Puncheon to strike a free-kick from the right hand side, but his effort beat everyone and went wide of the far post.

On the hour mark play was held up after Puncheon and McSheffrey collided in the middle of the field with the Leeds man requiring treatment that eventually saw him substituted for Neil Kilkenny. Puncheon received a booking during the stoppage as McSheffrey headed straight for the tunnel as the second Leeds player with his head bandaged.

Kisnorbo had to be alert to deal with Puncheon's cross on 67 as Saints forced two corners both taken by the number four which 'keeper Ankergren could only parry away.

With just under twenty minutes remaining Alan Pardew withdrew Barnard for Papa Waigo, the former Southend striker put in another workman like shift in attack which was unfortunate not to be rewarded with a goal.

In a bid to kick start their game, Leeds switched Becchio for Max Gradel on 76 minutes and within seconds of being on the pitch the forward received a caution for throwing Harding to ground, and was perhaps fortunate to avoid a more serious punishment for his bizarre actions.

Hammond went into Mr. Walton's notebook for kicking the ball away as further decisions went against the hosts, before Papa Waigo spun his way past Richard Naylor and got a shot away which Ankergren held on to.

Saints pushed on for a second which felt as though it was needed despite a solid defensive display and then again when the officials allocated five minutes of additional time for stoppages.

Despite a slightly nervous finish, Saints needn't have worried. The closest Leeds came during injury time was through Snodgrass' shot which blazed wide as Alan Pardew's men secured a precious three points against the Yorkshiremen.

Full Time: Saints 1-0 Leeds