Bournemouth came into the game in poor form having lost back-to-back games without finding the back of the net, but the Cherries hadn’t lost three successive games to nil since the end of the 2022/23 season, and as such, Andoni Iraola’s side would’ve been confident of ending that run.
They got off to a fantastic start too, taking the lead after just 17 minutes. Marcus Tavernier’s quick free-kick found Evanilson, allowing the Brazilian to hit a sweet first-time finish across goal and into the bottom corner to end his six-match wait for his first Cherries goal.
The visitors' heads seemed to drop after the goal, and they never really recovered in what quickly became a chastening first half for Russell Martin’s men.
They were punished again before the half-hour, as some brilliant play on the right wing from Antoine Semenyo saw him cut inside and find Lewis Cook, whose first-time shot took a deflection off Dango Ouattara before nestling in the bottom corner.
Things got even worse for Saints before half-time, finding themselves three goals behind as the sizzling Semenyo added his name to the scoresheet, finishing off a wonderful twisting run with a clinical finish to send the home fans into raptures.
Southampton started the second half in much better fashion though, and managed to get themselves an early goal as Taylor Harwood-Bellis directed Yukinara Sugawara’s inswinging cross into the far corner.
The visitors continued to be vulnerable at the back though, with Evanilson denied by Aaron Ramsdale as Bournemouth aimed to restore their three-goal advantage.
Iraola’s side began to look more dangerous again as the game drew nearer to its conclusion, and they went close again when Ryan Christie pounced on a loose ball on the edge of the penalty area before drilling a volley narrowly wide of the post.
That miss wouldn’t cost Bournemouth however, as they climb above Brentford and Manchester United thanks to their second win of the season. Southampton, meanwhile, remain rooted inside the drop zone having now failed to win any of their last 10 top-flight away matches.
"We watched a couple videos in the meetings over the weekend, we knew we can catch them with quick free kicks," Russell Martin told Sky Sports after the game.
The Southampton manager hammered his side for their poor first-half display.
"I didn't recognise our team. I'm usually proud of them for the courage (but) they showed no aggression, no courage, no intensity to play," Russell said.
"The second half, they show loads of fight, loads of courage but it's too late, so I'm hurt by the first half. Really, really, really disappointed by that," he added
Flashscore Man of the Match: Lewis Cook (Bournemouth)