It has been a mixed start for Chelsea so far this term, and they travelled to south to face a Bournemouth side on a high after overturning a two-goal deficit at Everton before the international break.
The Cherries were the better of the two sides before the break, and within four minutes they went within inches of breaking the deadlock when Marcus Tavernier’s long-range effort crashed back off the crossbar.
Evanilson and Antoine Semenyo then sent efforts off target before Robert Sanchez denied Justin Kluivert and Lewis Cook, but Bournemouth’s best opportunity to break the deadlock arrived shortly after the half-hour mark.
A poor Wesley Fofana backpass put Sánchez under pressure, and Evanilson beat him to the ball before pushing the ball past him to earn a penalty.
The club’s record signing stepped up himself as he looked to score his first goal for the club, but Sanchez was up to the challenge as he parried the spot-kick to safety.
There was the odd moment of quality from Chelsea, with Nicolas Jackson forcing a save from Mark Travers after some good play from Levi Colwill, but Enzo Maresca would ultimately have been disappointed with his side’s first-half display.
After the break, Bournemouth were initially on top, with Kluivert thwarted by Sánchez once more before Semenyo struck narrowly over and Ryan Christie hit the woodwork from the edge of the area.
In response, Maresca introduced Joao Felix, with Jadon Sancho having already come on at half-time, and those changes gave the Blues more control.
Andoni Iraola’s men looked to threaten on the counterattack, although to little effect, and that lack of pressure on the Chelsea goal ultimately proved costly.
Nkunku - who started the contest on the bench - was played in by fellow substitute Sancho, turned a couple of defenders and fired into the corner to send the visiting contingent into raptures.
Chelsea therefore emerged victorious in a match which featured 14 yellow cards - an all-time Premier League record. The Blues are unbeaten in three league matches, while Bournemouth have won just one match in all competitions this term.
Flashscore Man of the Match: Robert Sanchez (Chelsea)