Southampton took a significant step towards Premier League survival with a 1-0 win which increases the relegation concerns of south coast rivals Brighton.
Saints captain Pierre-Emile Hojbjerg earned the visitors victory at the Amex Stadium by scoring his first goal since December early in the second half.
Albion almost levelled when right-back Martin Montoya crashed a shot against the crossbar from the edge of the box with 18 minutes to go but Chris Hughton's side, who grabbed a last-gasp equaliser at St Mary's in September, were unable to salvage a draw.
The result moves Saints level on 33 points with the Seagulls, five above the drop zone ahead of 18th-placed Cardiff's clash with Chelsea on Sunday.
Southampton were able to call on the services of top scorer Danny Ings for the first time in almost two months following his recovery from a hamstring problem.
The on-loan Liverpool man, who has eight goals in all competitions this term, was left glaring at referee Michael Oliver in the 23rd minute after going down in the box under a challenge from Montoya while trying to get on the end of James Ward-Prowse's cross from the right.
Due to FA Cup fixtures and an international break, the visitors had not played since upsetting Tottenham at St Mary's three weeks ago.
They showed more attacking intent than their opponents during an uneventful and edgy opening period which suggested both sides were more concerned with not losing.
Ings was later denied by a superb block from Bernardo having found space in Albion's 18-yard area, while Southampton winger Nathan Redmond had earlier fired a stinging shot straight at Brighton goalkeeper Mathew Ryan from a tight angle.
With next Saturday's Wembley FA Cup semi-final against Manchester City on the horizon, Albion boss Hughton has been keen to stress that top-flight safety remains the priority.
Once again missing the creative talents of injured 2017/18 player of the season Pascal Gross, the Seagulls struggled to carve out opportunities as they went in search of a third successive league win.
And they could have few complaints about conceding eight minutes after the restart.
Redmond's driving run and perfectly-weighted pass slipped Hojbjerg in on goal and he produced a composed poke past Ryan and into the bottom right corner in front of the sold-out away end.
Falling behind briefly sparked Brighton into life, culminating in Anthony Knockaert sending a powerful drive past the left post.
But the home side could easily have gone further behind moments later as Lewis Dunk blocked Ryan Bertrand's low effort inside the six-yard box with Redmond lurking for a tap-in.
Brighton were inches away from an equaliser in the 72nd minute when Spaniard Montoya, whose last goal came for Valencia in January 2017, rattled the woodwork from the edge of the box.
The home fans were then unhappy with match official Oliver when Davy Propper went to ground in the box following a nudge from Denmark midfielder Hojbjerg after Saints keeper Angus Gunn failed to hold a ball into the box.
Southampton were pinned back for the majority of the nervy closing stages, with Seagulls substitute Jurgen Locadia finally producing the hosts' first attempt on target six minutes from time.
Despite the heavy pressure, Ralph Hasenhuttl's men doggedly held on for a vital three points to end a run of three successive Premier League draws between the two clubs.
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