Chelsea secured their fifth Premier League title with a dramatic late victory at West Brom.
Substitute Michy Batshuayi scored in the 82nd minute to secure the vital win, sliding in to turn home Cesar Azpilicueta’s cut-back from close range.
After nearest rivals Tottenham lost against West Ham on 5 May, Chelsea needed only two wins from their final four matches to take the trophy.
They convincingly beat Middlesbrough 3-0 on Monday and wrapped things up with victory at The Hawthorns.
Chelsea were made to work hard on the night by a resolute West Brom.
The Blues had 14 shots on goal in the first half, including Cesc Fabregas’ bending effort which went wide.
Victor Moses struck through the legs of James McClean, only to be denied by a brilliant save from Ben Foster after the break.
West Brom took control of the match, as Salomon Rondon’s shot deflected wide after a rapid counter-attack and Nacer Chadli clipped his effort past the post.
But then Batshuayi scored his second league goal of the season, sending the Chelsea players and manager Antonio Conte into frenzied celebrations.
Conte becomes only the fourth manager to lift the Premier League trophy in his first season in England, emulating Jose Mourinho in 2004-05, Carlo Ancelotti in 2009-10 and Manuel Pellegrini in 2013-14.
And the Italian has claimed a fourth successive league title as a manager – adding to the three Serie A trophies he won with Juventus.
Former England midfielder Jermaine Jenas told BBC Radio 5 live: “These celebrations are unbelievable.
“It is thoroughly deserved. They have been the best team this season.
“The changes Conte has made to change their season around can’t be underestimated.
“When their backs have been against the wall tonight, they defended well. This game typified Chelsea’s season. How many winners they have in their team makes them special.
“But tactically, individually, what Conte has done with these players and to bring them together is sensational.”
Chelsea are the first club to win the English top-flight title on a Friday since Arsenal at Anfield in 1989.
Conte is the fourth Italian manager to win the English top-flight title after Ancelotti, Roberto Mancini and Claudio Ranieri.
Chelsea scored with their 23rd shot of the match at West Brom
A Belgian player has scored the title-deciding goal in each of the past three Premier League seasons (Batshuayi v West Brom in 2016-17, Eden Hazard v Tottenham in 2015-16 and v Crystal Palace in 2014-15).