Chelsea power rankings: Havertz explodes, Lukaku crashes
Trevoh Chalobah is the Chelsea player who has improved the most over the past six months, while captain Cesar Azpilicueta is the Chelsea player who has declined the most over the same time period, according to SciSports.
Using in-game data to calculate the performance of every Chelsea player, Chalobah has statistically improved the most and Azpilicueta has suffered the opposite fate.
The most improved Chelsea players
Chalobah spent last season on loan at Ligue 1 club Lorient, but returned in pre-season and impressed Thomas Tuchel enough to give him a chance in the first-team. He scored on his Premier League debut against Crystal Palace on the opening day of the season, and has made 26 appearances in all competitions this season.
The defender has suffered with a few injuries this campaign, but his time on the pitch has seen him improve his SciSports skill level the most.
Second on the list for Chelsea's most improved players over the last six months is Callum Hudson-Odoi. The winger suffered an Achilles injury before Frank Lampard took charge, and since then hasn't been able to establish himself as a first-team regular. However, this season that has changed as Tuchel has placed trust in the young Englishman.
He has still only played 28 games in 2021/22, but that's been enough to see his skill level improve by 8.2. Hudson-Odoi has contributed nine goals this season.
The third-most improved player has been Ben Chilwell. The left-wing-back may have been injured since the end of November, but his work in October and early November was enough to see his skill level rise drastically. he has only played six games all season due to injury and recovering from Euro 2020 late, but during that time he scored three goals and assisted one to help Chelsea to the top of the Premier League at the time.
Kai Havertz sits fourth on the list following his transformation into a striker. The Germany international played there infrequently last season, but is now Tuchel's first choice option through the middle. He has scored 11 and assisted five this season, with one of those goals the winner in the Club World Cup final.
Thiago Silva rounds off the top five of most improved players with the Brazilian proving to be ageless. He has solidified the Chelsea backline, and is one of the first names on the teamsheet.
The Chelsea players who have declined the most
On the other hand, Azpilicueta hasn't had such success. In fact, the Spaniard has declined the most of any Chelsea player. A clause in his contract at the club has been activated, which means he will stay at Chelsea next season, but Azpilicueta hasn't enjoyed a statistically fruitful 2021/22 campaign.
Competing with Chalobah for a place in the team has meant Azpilicueta will end the season with his fewest ever Premier League appearance tally for a single campaign unless he plays in every single game left.
This has meant he has dropped off his level, according to SciSports.
Second on the list of Chelsea's biggest declining players is Marcos Alonso. The left-wing-back has filled in for Chilwell, but hasn't managed to replicate the Englishman's output.
Despite his attacking endeavour, he hasn't scored in the league since the opening day of the season.
Romelu Lukaku is the Chelsea player who has declined the third-most over the last six months, with Tuchel favouring Havertz instead. He scored in back-to-back games at the end of December, but hasn't found the back of the net in the Premier League since. Chelsea's record signing is now playing back-up to Havertz and hasn't started any of the past four league games.
Despite three goals in 2022, Hakim Ziyech is fourth of the players to decline the most, with his inconsistency costing him. Although he started the year well, Ziyech has started just six of the past 11 league games, and his form before Christmas was fairly patchy.
Timo Werner finishes off the five, having declined by 1.0 skill rating. The German has scored just one Premier League goal this season, which came back in October. He has also contracted coronavirus in the past six months, which caused a lengthy absence.
Chelsea Power Rankings over the past six months