Arsenal goalkeeper Petr Cech has criticised Bayer Leverkusen for lacking "important values" with a message posted on social media.
The German side's Twitter account appeared to question why Cech was selected in goal over Bernd Leno for Sunday's 2-0 defeat to Manchester City.
Leno joined the Gunners in a £19m transfer during the summer transfer window, but has been made to wait for his competitive bow.
In a tweet published shortly after the game, Bayer joked that they "might know a guy" who can replace Cech in goal after the experienced stopper came close to conceding a comical own goal.
The 36-year-old did not see the funny side, however, and has now hit back.
"@Arsenal we share important values which make us a big club not only on the football side," he said. "Fair competition, professionalism and sportsmanship are the biggest ones you teach young footballers and it's sad to see when other clubs don't share the same values. .@bayer04_en"
.@Arsenal we share important values which make us a big club not only on the football side . Fair competition, professionalism and sportsmanship are the biggest ones you teach young footballers and it's sad to see when other clubs don't share the same values. .@bayer04_en
— Petr Cech (@PetrCech) August 13, 2018
Bayer apologised for the tweet and wished both Cech and Arsenal well for the rest of the season.
