Match ends, Southampton 2, Fulham 0.
Southampton moved out of the Premier League relegation zone and left Fulham 10 points from safety with a comfortable win at St Mary's.
Ralph Hasenhuttl's side saw just 36% of the ball in the opening 45 minutes but led 2-0 thanks to Oriol Romeu's finish after a poor Sergio Rico punch and James Ward-Prowse's follow-up when Nathan Redmond's shot was saved.
Fulham's Aleksandar Mitrovic fired over the bar from a narrow angle with the score at 1-0 and he again lifted over when put through on goal a minute after the interval.
Ryan Babel shot onto the bar via a deflection for Claudio Ranieri's side but they failed to muster a meaningful rally and the Italian manager's substitution of Tom Cairney drew boos from away supporters.
Fulham are 19th, 10 points adrift of Saints in 17th.
'Should-win' becomes easy win
Hasenhuttl branded the fixture "must-win" for Fulham and "should-win" for his own side.
Despite being winless in four and having just six home wins in 37 fixtures at St Mary's coming into the fixture, Saints looked confident and energised.
Ryan Bertrand was a regular threat and it was his super delivery which won the corner that led to the opener, Romeu firing a low effort into an exposed net after Rico had only punched to the edge of the area.
Fulham, the only Premier League side without an away win this season, found little in response and Ward-Prowse - the game's stellar performer - was first to react after Redmond's low effort from 18 yards was palmed out.
There were other noteworthy positives in the way Romeu and Pierre-Emile Hojbjerg broke up play with ease, each winning possession back 11 times. Romeu also kept possession better than any player on the pitch, completing 94% of his 49 passes.
It was composed and relatively routine for the home side. After an uplift in form following Hasenhuttl's December appointment, Saints had shown signs of decline in recent weeks but this win moves them out of the bottom three at a timely point with fixtures against Manchester United and Tottenham to come next.
'You don't know what you're doing'
A second-half moment featuring Cairney summed up Fulham.
The Scottish midfielder battled to win a ball in a feisty exchange with Ward-Prowse and then out-muscled another Southampton player to win a corner, only for Joe Bryan to float the delivery straight out of play.
The Cottagers were clearly trying but moments of quality were non-existent and Cairney's substitution saw fans react angrily. Banners criticising the club's hierarchy were unfurled, while another hailing former manager Slavisa Jokanovic was also held aloft.
Chants of "you don't know what you're doing" were aimed at the manager, who later said his team will "fight until it is mathematically impossible" in their battle against the drop.
Any escape will undoubtedly require magic from Mitrovic, who remains a constant target for long balls. But defeat at St Mary's showed if his admirable hold up play comes up short, the Cottagers have little else to offer.
Shots over the bar when Mitrovic would have expected to work the keeper either side of half-time ultimately ensured there was no way back, and Babel's shot onto the woodwork late on was against the run of play.
Despite their lowly league position and urgent need for points, Ranieri's side only had four touches in the Southampton area in the second period.
They have not won an away league fixture since the final day of the Championship season in May and now face Chelsea, a Leicester side boasting a new manager, Liverpool and Manchester City in their next four games.
Relegation is seemingly rapidly approaching.
Man of the match - James Ward-Prowse
Saints' improving home form - stats
- Southampton have won two of their past four Premier League home games (D1 L1), as many wins as they managed in their previous 21 at St Mary's (D10 L9
- Fulham have lost seven of their past eight Premier League games (W1), conceding at least twice in all eight.
- Southampton have beaten a newly promoted team for the first time since May 2017 (2-1 against Middlesbrough), having failed to do so in their past 10 Premier League games against such teams (D5 L5).
- Southampton are now unbeaten in their past 20 home league games against Fulham (W14 D6), since a 2-21loss in October 1935 (second tier). Only against Coventry (22 games) have they ever had a longer unbeaten home run in their league history.
'A win without mistakes' - manager reaction
Southampton manager Ralph Hasenhuttl speaking to Match of the Day: "It was a very important win for the whole club. It was a professional performance and we switched the speed at the right moment which is why we scored.
"It's the first clean sheet in a long time and we showed we can play without mistakes."
Fulham manager Claudio Ranieri told Match of the Day: "It was not enough. We tried our best but every time we have to say the same thing - the first time in front of goal, the opponent scored.
"We have to continue to fight until it is mathematically impossible. The confidence is not at the maximum level and it is not easy to react but I want them to react soon."
Southampton face a trip to Manchester United on Saturday (15:00 GMT), while Fulham host Chelsea in a west-London derby on Sunday (14:05).
- 10AustinSubstituted forLongat 64'minutes
- 6McDonaldBooked at 62minsSubstituted forR Sessegnonat 69'minutes
- 29Zambo Anguissa
- 10CairneySubstituted forViettoat 69'minutes
- 3R Sessegnon
- Anthony Taylor
- Shots on Target
Second Half ends, Southampton 2, Fulham 0.
Foul by Håvard Nordtveit (Fulham).
Shane Long (Southampton) wins a free kick on the left wing.
Attempt saved. Calum Chambers (Fulham) right footed shot from outside the box is saved in the bottom left corner.
Attempt blocked. Ryan Sessegnon (Fulham) left footed shot from outside the box is blocked.
Delay over. They are ready to continue.
Delay in match Ryan Bertrand (Southampton) because of an injury.
Foul by Luciano Vietto (Fulham).
Ryan Bertrand (Southampton) wins a free kick in the defensive half.
Attempt missed. André-Frank Zambo Anguissa (Fulham) left footed shot from outside the box misses to the left following a corner.
Corner, Fulham. Conceded by Shane Long.
Corner, Fulham. Conceded by Jan Bednarek.
Foul by Ryan Babel (Fulham).
Jannik Vestergaard (Southampton) wins a free kick in the defensive half.
Foul by Aleksandar Mitrovic (Fulham).
Oriol Romeu (Southampton) wins a free kick in the defensive half.
Attempt missed. Shane Long (Southampton) right footed shot from the right side of the box misses to the left. Assisted by James Ward-Prowse.
Offside, Fulham. Denis Odoi tries a through ball, but Aleksandar Mitrovic is caught offside.
Attempt blocked. Ryan Babel (Fulham) left footed shot from the centre of the box is blocked.