Ward-Prowse opened the scoring after the lively Nathan Tella had been brought down by Ethan Ampadu and Adams made the points safe with a scorching half-volley on 49 minutes.
Southampton eased their relegation fears at the expense of Sheffield United whose own Premier League race now looks run as they were sunk by one of their own, Che Adams.
Adams owes his professional career to United who plucked him from non-league Ilkeston in 2014. But football isn’t a sentimental business and the forward showed little gratitude with an emphatic finish at the start of the second half that sealed a deserved away victory.
Southampton had only picked up one point from their previous nine games but were still far too good for a Blades team who looked resigned to their fate despite a rare midweek win against Aston Villa.
Che Adams slammed home a brilliant half-volley after coming on for Danny Ings early on
Ings came off on 13 minutes after pulling up with an injury following Ryan Bertrand's free kick
Despite losing their main striker Danny Ings to injury after 13 minutes, Adams coming on his place, Southampton were worthy of taking the lead after 32 minutes when Ethan Ampadu fouled the excellent Nathan Tella and James Ward-Prowse dispatched the penalty.
David McGoldrick missed the home side’s best chance to level of half-time showing why The Blades are the lowest scorers in the division before Adams showed how it should be done after 49 minutes, profiteering from a botched clearance by John Lundstram.
Chris Wilder withdrew both his starting strikers, McGoldrick and Rhian Brewster who hasn’t scored at all this season following his £23million move from Liverpool, but nothing seemed to work and in the end, Southampton could have won by more with Tella denied by Aaron Ramsdale and Takumi Minamino missing the target from six yards.
Nathan Tella put in a lively display and won a penalty after being fouled by Ethan Ampadu
James Ward-Prowse dispatched the spot kick to bag his sixth league goal of the campaign
Adams' strike four minutes into the second half then took the game beyond Sheffield United
SHEFFIELD UNITED (3-5-2): Ramsdale; Baldock, Ampadu, Bryan; Bogle, Lundstram, Norwood (McBurnie 46), Fleck, Stevens; Brewster (Sharp 68), McGoldrick (Mousset 58).
Subs not used: Burke, Lowe, Ndiaye, Maguire, Foderingham, Osborn.
Goals: None
Yellow: Ampadu, Bogle, Fleck, McBurnie
Red: None
Manager: Chris Wilder
SOUTHAMPTON (4-4-2): Forster; Walker-Peters, Bednarek, Vestergaard, Bertrand; Armstrong, Diallo, Ward-Prowse, Minamino (Djenepo 88); Ings (Adams 13), Tella (Redmond 77).
Subs not used: Salisu, Chauke, Jankewitz, N'Lundulu, McCarthy, Stephens.
Goals: Ward-Prowse 32, Adams 49
Yellow: Tella, Armstrong, Vestergaard
Red: None
Manager: Ralph Hasenhuttl
Referee: Paul Tierney
‘It was the first time for a long time we had players in the right positions and we looked a completely different side,’ said Saints boss Ralph Hasenhuttl celebrating his hundreth game in charge.
‘Che sometimes doesn’t take the easy chances but he seems to make the tough ones! It was a brilliant goal and he did well for us.’
In contrast, things look bleaker than ever for United who are now 12 points from safety with only 10 games left for them.
Last season’s top-half finish is a distant memory for the team now lying bottom and manager Chris Wilder accepted: ‘The better team won. We looked tired in mind and body and Aaron kept the scoreline down in goal.
‘Our quality in the second half was extremely poor. We have the ball away cheaply and their second goal came from mistakes by us,
‘If you are looking at this season, most of our players have been four, five or six out of 10. The player of year award isn’t going to be contested by many.’
Things didn’t look too clever early on for Saints when Danny Ings limped off after 13 minutes with a muscular problem that could see him ruled out for a few weeks.
But Adams – who was sold by Wilder to Birmingham in 2016 – came on and 21-year-old Nathan Tella emerged as the game’s outstanding forward in only his second Premier League start.
Rhian Brewster is still searching for his first goal for the Blades after his move from Liverpool
Takumi Minamino could have made the scoreline even more emphatic - but slotted just wide
Oli McBurnie squares up to Jannik Vestergaard after John Fleck's foul on Che Adams late on
Tella had already fired two shots at goal before his pace forced Ethan Ampadu into a lunge that earned Southampton a penalty after 32 minutes. With Ings off the pitch, skipper Ward-Prowse took responsibility and coolly sent Aaron Ramsdale the wrong way.
United are the division’s lowest scorers and you could see why when McGoldrick was sent clear on the stroke of half-time and foolishly tried to chip 6ft7ins Fraser Forster. The goalkeeper comfortably gathered.
Chris Wilder sent on Ollie McBurnie but his side fell further behind before the big striker could make an impact.
Adams initially had a shot parried by Ramsdale but when John Lundstram tried to clear, Ryan Bertrand intercepted. The ball dropped to Stuart Armstrong who fed Adams to lash home from 22 yards.
It was his first goal since December, also against The Blades, and four of his last seven have been against his old club.
Tella looks a real prospect for Saints. ‘I was always convinced about this guy. For me at the moment, he is the most interesting player from our youth,’ said Hasenhuttl.
‘He can be a threat for defending teams. He is quick and goes for every ball. I think the mentality of this guy, he is never nervous.’
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