Football fans tend not to be forgiving of players who transfer to rival clubs.
Just ask Luis Figo, the former Barcelona captain who left for Real Madrid in 2000 and was pelted with objects - including a butchered pig's head - when he played at Camp Nou two years later. The Catalans even refused to let him play in an exhibition match between Barcelona and Juventus legends a little over a fortnight ago.
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Petr Cech, however, should not be afforded similar treatment for his transfer to Arsenal - which has predictably upset some Chelsea fans.
While it may be a minor blow to the Blues' title defence, it is certainly not an act of betrayal from a man who continually exceeded all expectations in a trophy-laden 11-year stint at the club.
A matter of life or death
It is easy to forget that Cech literally nearly died when a collision with Reading's Stephen Hunt caused his skull to fracture and two loose pieces to dig into his brain. Had they gone any deeper before being removed, the injury would have been fatal.
However, what is most remarkable is how he returned to Chelsea's lineup in January 2007 - three months after the incident - despite medical experts having written his season off.
This resilience played a huge part in Cech's Chelsea career. Few have forgotten his heroics against Barcelona and Bayern Munich in Chelsea's 2011/12 Champions League winning campaign, but many fail to remember that he was being berated for his form a mere five months earlier.
Cech's persistence was evident during good times, as well as bad. During the 2004/05 season, he was at his virtually unstoppable best - not conceding a goal for 1025 consecutive minutes of Premier League football and playing a key role in his side keeping their tally of league goals conceded to a mere 15.
Initially signed by Claudio Ranieri as backup for Carlo Cudicini, Cech wasted no time in taking the Premier League by storm and - despite significant adversity - rarely looked back.
It is little surprise that he responded to being dropped in favour of Belgian goalkeeper Thibaut Courtois by knuckling down and performing well when called upon.
The majority of Chelsea fans are likely to treat Cech with similar respect when they come up against Arsenal - and so they should.