Diego Costa’s deflected shot gave Chelsea the lead early on at the Vitality Stadium, before Eden Hazard made it 2-0 with a superb finish from N’Golo Kante’s pass.
Joshua King pulled a goal back for the visitors before half-time, but Alonso had the final say when he curled home a delightful free-kick in the second half to wrap up the three points for the Blues.
Conte was delighted by Alonso’s performance and singled out the Spaniard for special praise after the game.
“Marcos is playing a really good season and it’s great for him to show his quality with the free-kick,” Conte told BT Sport. “I’m happy for him but I’m happy above all for the team.”
Alonso has been a regular fixture in the Chelsea team this season since his arrival at the club from Fiorentina last summer.
The 26-year-old Spaniard has scored five goals and made two assists in 26 Premier League games so far this season.
He will be hoping to feature when the Blues take on Manchester United at Old Trafford next Sunday.
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