Chelsea, which is known as a recognizable football club in the world, has won the Premier League five times and the Champions League twice since 2003. Contributing to that glory, some of the greatest Chelsea players in the world have come to Stamford Bridge, which also paved the way for many unknown players to become the club's legends. These Chelsea Players moved to a rival.
Understandably, footballers want to advance in their careers or simply seek a new challenge in a new club. That's why moving to another club is so common nowadays. Still, it is not very common when they leave their club, which brought them glory, to join a direct rival. This in turn angers the fanbase and shocks the world, let's scroll down and check them out! These Chelsea players move to rival Premier League clubs.

#1 William Gallas to Arsenal

Source: planetfootball/ @shabbany/ Twitter

William Gallas, a French defender, was known for the trade that brought Ashley Cole from Arsenal to Chelsea. Gallas had a falling out with former Chelsea head coach Jose Mourinho in 2006. So he moved to Arsenal as the Blues were interested in signing Cole and considered Gallas as a trade for him. The center-back played more than 100 Premier League matches for the Blues but failed to make an impression. Gallas decided to join rivals Tottenham Hotspur as a free agent in 2010 after falling out with the Arsenal board over his salary.

#2 David Luiz to Arsenal

Source: planetfootball / mirror

Brazilian defenders played a key role in Chelsea's success for the majority of the last decade. He came to Stamford Bridge in 2011 and helped the club win the first UEFA Champions League title in 2012. He won the Premier League, the Champions League, two Europa Leagues, and two FA Cups during his time at the Blues.
Luiz was sold to Arsenal in 2019 where he struggled because of his injuries. Still, he's actually gone from zero to hero at the Emirate, winning the FA Cup just weeks after a dreadful performance against Man City in the Premier League.

#3 Petr Cech to Arsenal

Source: thescore / express

Petr Cech is statistically the best goalkeeper who won four Premier League crowns, four FA Cups, three League Cups, the Champions League, and the Europa League in 494 appearances with the Blues. He later moved to the Emirates, where he won another FA Cup while also losing the finals in the League Cup and the Europa League. Cech has since retired and is now working as a technical and performance advisor at Stamford Bridge.

#4 Frank Lampard to Manchester City

Source: chinadaily / english.aawsat

Without a doubt, Frank Lampart is a Chelsea legend. The midfielder scored 211 goals and had 150 assists under his belt for the Blues. He also won many trophies during his 13 years at Chelsea. Among his many accomplishments, he won three Premier League titles and one Champions League.
Following his final season at Chelsea, Lampard played for Manchester City for a single season. In the summer of 2014, he joined the MLS team New York City FC without a transfer fee. When Manchester City took on Chelsea, Lampard scored, but he did not celebrate as an act of respect.

#5 Juan Mata to Manchester United

Source: football.london / rare-gallery

Juan Mata came to Chelsea in 2011 from Valencia, where he won the UEFA Champions League in his first season and the UEFA Europa League in his second.
And Mata made a bizarre decision when he was awarded the Blues' Player of the Year award twice in 2012 and 2013.