Jermain Defoe's return to Bournemouth was spoiled by Watford, who struck two late goals to condemn Eddie Howe's team to their second straight Premier League defeat.
Goals from summer signing Richarlison, who prodded in from inside the six yard box, and substitute Etienne Capou were enough for the visitors to triumph on the south coast.
Capou was on the pitch for just minutes before he sealed his side's first Premier League win of the season.