Evanilson scored his first AFC Bournemouth goal while Dango Ouattara and Antoine Semenyo were also on target as south-coast rivals Southampton were brushed aside in a routine 3-1 victory.
Brazilian forward Evanilson steered past ex-Cherries goalkeeper Aaron Ramsdale on 17 minutes at the Vitality Stadium on Monday thanks to Marcus Tavernier's quick thinking.
Ouattara was credited with Bournemouth's second and Semenyo clinched the third in a wonderful first-half performance with a fine solo effort.
Taylor Harwood-Bellis reduced the areas early in a second half in which Southampton, to their credit, showed some fighting spirit, but it could not repair the damage of a disappointing opening 45 minutes.
Bournemouth's first home win of the season moves them 11th in the Premier League standings, while Southampton are 19th with just a solitary point from six matches.
How the match unfolded
The hosts caught Saints napping for the opener when Tavernier dinked a quick free-kick into the area and Evanilson expertly guided his volley into the bottom-left corner.
It sparked a period of dominance from the hosts and they doubled their lead when Lewis Cook's shot, from Semenyo's cutback, hit Ouattara and diverted beyond Ramsdale.
Semenyo then got in on the act himself, shimmying this way and that on the right of the penalty area before drilling a lovely, low finish into the bottom-left corner in the 39th minute.
Harwood-Bellis stooped low to nod in from Mateus Fernandes' deflected cross five minutes after the restart, having been brilliantly denied by Kepa Arrizabalaga just prior, to give Southampton hope.
Substitute Ben Brereton Diaz bent an effort wide of the right post and brilliant defending from Milos Kerkez denied Yukinari Sugawara a simple finish as Southampton fought in vain to create a nervy ending.
Bournemouth forwards' delight as Evanilson gets off the mark
Bournemouth forked out a reported £40.2million to Porto for Evanilson in the summer transfer window as they sought a replacement for Dominic Solanke, who was sold to Tottenham Hotspur.
The 24-year-old failed to score in his first four Premier League appearances and missed a penalty as the Cherries fell to a 1-0 defeat to Chelsea earlier this month.
But there were no signs of a forward lacking in confidence when he brilliantly steered home after showing an almost telepathic understanding with Tavernier.
Andoni Iraola, watching from the stands as he served a touchline ban, will hope it can spark a run of form for Evanilson, who was also denied in a one-on-one in the second half.
Evanilson will certainly get chances if Ouattara and Semenyo can continue to show the sort of form they did here as Bournemouth earned a first home win over Southampton since 2016.
Both wingers were a constant menace down the flanks, with the former putting in a couple of excellent deliveries from the byline, while the latter was influential for the second before brilliantly lacing in his third league goal of the campaign.
They may no longer have Solanke but there is plenty of talent to admire in this Cherries front line.
Saints just can't get marching
One of the pre-match narratives surrounded Ryan Fraser's first return to the Vitality Stadium since an acrimonious exit in 2020.
The Saints winger was loudly booed every time he went near the ball but he was denied by Kepa after Maxwel Cornet had already seen an effort deflected wide as part of a bright start from the visitors.
But soon enough chants of "Fraser, what's the score?" were ringing out from the terraces as Southampton - still winless since returning to the top flight - completely lost control of the match.
While Evanilson will rightly take credit for a fine opener, question marks will be asked of how the Southampton defence just completely lost concentration, too.
Theirs will not be the only defence to struggle against Semenyo and Ouattara this season, but familiar failings reared their head in a poor first-half performance.
A triple substitution at the break, which saw Brereton Diaz, Joe Aribo and Ross Stewart enter the fray, brought about a spirited second-half showing, which yielded Harwood-Bellis' goal.
In truth, though, the damage was done by a first-half horror show that will leave boss Russell Martin needing to go back to the drawing board.
Club reports
Match officials
Referee: Michael Oliver. Assistants: Stuart Burt, Dan Cook. Fourth official: Simon Hooper. VAR: Paul Tierney. Assistant VAR: Harry Lennard.
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