Some things don't change, and new Chelsea boss Antonio Conte would have been made well aware of that very early on in Chelsea's first pre-season friendly against Austrian side Rapid Vienna at their new Allianz Stadion.
No doubt, Conte was well are of Chelsea striker Diego Costa's fiery temperament before his arrival at Stamford Bridge, but just incase it had slipped from the Italian's mind for a moment, the Spain striker took no time at all to remind his boss.
Just 14 minutes into the Blues' fixture against Vienna, the 27-year-old was rattled after some apparent jostling between himself and opponent Srdjan Grahovac. Costa pushed the Bosnian away before seemingly not wanting to let him get out of his grasp, by pulling his shirt.
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However, the hot-headed striker was not done there, and then pursued the referee for a word... or two. Swinging his arms and clearly angered by Grahovac's actions, although it didn't earn Costa's opponent a yellow card; taking into account it was a 'friendly' fixture.
The worry for Conte will be how Costa will react when more rash challenges in competitive fixtures come in, over the coming months, with the Premier League season just around the corner.
But perhaps the fact that Chelsea will not be competing in Europe in the upcoming season will help Costa to avoid the dirty tricks of fellow European nations. Or, alternatively, the striker may not be at the club at all.
Atletico Madrid are seemingly still pursuing the Brazil-born striker, with club president Enrique Cerezo admitting he still admires the player that left the club for the Blues in 2014.
Costa has endured a tough time in west London, having been branded a 'rat' by some fans, after Jose Mourinho was sacked at the back end of last year. And some reports have claimed the Spain star wants to return to La Liga.
Despite his outbursts, as Conte has witnessed in his first game in charge, the Italian is keen for the Spaniard to be a part of his plans. Costa produced one of very few clear-cut chances for Chelsea on Saturday afternoon, narrowly heading over Papy Djilobodji's ball after 65 minutes.
It waits to be seen whether Costa's angry outburst was the final memorable moment in the 27-year-old's relatively short Chelsea career. It's about the only attribute Blues fans won't miss about their frontman.
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