Diego Costa is regarded as one of Chelsea's most important players and remains their leading scorer this season, but stats from Opta show that his form has taken a dip since his offer from Chinese Super League clubTianjin Quanjianin January.
The Spain international ultimately chose to decline the offer and remainat Chelsea to compete for the Premier League title and FA Cup glory, but he wasoffered a staggering £30 million-per-year contract, which would have almost tripled his salary and may have proved to be a distraction.
Did his head get turned by the offer? Well, he was subsequently dropped against Leicester City and contract negotiations with the club have slowed -it was also then that hesuffered his longest goal drought of the season.
His most recent performance against Crystal Palace was one of his worst displays of the season, missing key chances and only managing to get two of his nine attempts on target.
However, before that he had scored three goals in three games, but most were late on in matches with less riding on them,or against lesser opposition as he looked to get himself back to his early season form.
He remains key ahead ofChelsea's final months of the season and they fought to keep him for a reason,although the data shows that his form has dipped since the transfer window, as Romelu Lukaku and Harry Kane have surgedahead of him in the goalscoring charts.
His goals-per-game has dropped from 0.7 to 0.4in the league, while he was registering 0.26 assists per game but has not nowprovided a killer passsince before the transfer saga.His shots-per-game is down slightly as well, while his conversion rate has gone down to17.65% from10.34%.
Costa is also creating fewer chances for his team-mates in recent weeks, as he is only getting0.3 per game now, while before 14 January, when the story broke, itwas 1.5 chances created per game. He is also winning fewer fouls sinceTianjin's offer - down from2.6 per game to 2.4.
Despite his dip in form, it may be harsh to question his work-rate as he is actually winning more duels, both in the air and on the ground. He is also fouling more now, which could suggest that frustration has crept into his game since his big money offer, or that he is workinghard to improve his recent form. It could also be a combination of the two.
In person, it is plain to see that Costa's form has declined slightly, which is normal over the course of the season, but thestatsshow a correlationto his link to China.
Luckily for Antonio Conte and Chelsea,other players have stepped up in recent weeks,with the likes ofEden Hazard putting in all-star performances. Goals have been coming in from all over, from Gary Cahill andN'Golo Kante to Marcos Alonso and Pedro.
Whether Chelsea keep Costa or lose him in the summer, with interest from the Chinese Super League still high,Chelsea will target signing another forward.
Lukaku, who has become the favourite to win the Premier League's golden boot, remains a Chelsea target after they tried and failed to secure him last summer.Real Madrid's Alvaro Morata is another who continues to interest Conte, as well asa host of younger playersincluding Celtic's Moussa Dembele and Ajax's Kasper Dolberg.
Conte has stated he is "confident" that Costa will stay, while Costa himself told ESPN Brasil that "everyone [at Chelsea] is on the same page," which suggests any problems between him and the club are on hold during the hunt for trophies.
In the meantime, Chelsea could do with the revitalisation of Costa to compete with their summer target Lukaku in the golden boot race, with the Everton striker going two ahead of Chelsea's frontman in recent weeks.
Costa's current form isn't terrible, but it isn't great, which is what Chelsea need him to beif they are to earn the Holy Grail of a league and cup double in Conte's first season in charge of the club.