Southampton opened up a five-point lead at the top of the Championship with a narrow win over second-placed West Ham.
Jos Hooiveld's goal was enough for Saints as he headed home Daniel Fox's corner on the stroke of half time.
It maintained Southampton's 100% home record and came in front of a St Mary's record crowd of 32,150.
West Ham had chances to level, with Sam Baldock shooting wide and Mark Noble hitting the post as they lost away from home for the first time this term.
The visitors started brightly with Matt Taylor testing Kelvin Davis with a low drive inside the opening minute. Dean Hammond then shot over from distance twice for Southampton.
West Ham were forced to make an early substitution when Taylor limped off, to be replaced by Frederic Piquionne, with what looked to be a recurrence of a calf injury.
Richard Chaplow should have done better for the home side with a close-range volley before Kevin Nolan watched his 22-yard, curling shot fly inches wide.
Baldock looked set to get his name on the scoresheet in the 36th minute but his hooked effort from eight yards was well blocked by the legs of Davis.
That sparked Southampton back into life and, after David Connolly saw a first-time volley gathered by Manuel Almunia, they opened the scoring.
Fox's corner from the right picked out Hooiveld and the on-loan Celtic defender powered in a header.
The home side continued to dominate after half time, with a succession of corners, but Baldock found himself one-on-one with Davis before curling the ball wide as the game opened up.
A slip from Papa Bouba Diop allowed Connolly to race forward and bend a shot just wide, but West Ham kept pressing as Nolan brought another stop from Davis.
Chaplow was not too far away with an angled drive and Guly Do Prado curled an effort wide then had a shot blocked.
In a frantic finish, Noble saw a free-kick tipped on to the roof of the net and, from the resulting corner, his cross flicked off the head of a defender and came back off the far post but Southampton held on.
Southampton manager Nigel Adkins:
"West Ham were in the Premier League last season, their aspiration is to go straight back up and they are favourites to do that.
"We also have that aspiration and after 12 games of the season we are top of the league and are there on merit.
"We kept a clean sheet, played some good football, created opportunities and scored a good goal from a set play so I am pleased with the three points.
"We have got a lot of belief at the club and are trying to play good football."
West Ham manager Sam Allardyce:
"We knew Southampton would be dangerous coming forward and I wanted to nullify their attacking strengths.
"The first half was very tight and we created some chances so were disappointed to concede right before half-time.
"This is not an easy place to come and on another day we would have got something out of it."