The former Chelsea and Atletico Madrid striker joined Brazilian side at the start of the year and will turn 36 next month.
However, it’s clear that his passion for the game is still as strong as ever.
Costa was taking part in a cup match for Gremio’s B team against Juventude B, a game that was made up of mostly U20 players.
And in what is unlikely to come as the most surprising piece of news of the day, he was sent off, MailOnline reports.
The forward was far from happy with a late challenge and proceeded to confront the player who challenged him, grabbing his shirt and putting his arm round him as he pushed him backwards.
Both players were shown their marching orders for their part in the incident with the clip quickly doing the rounds on social media.
In a sparkling club career, Costa has scored 192 goals for the likes of Atletico Madrid and Chelsea and has also turned out for the Brazil and Spain national teams.
He won the Premier League title twice with Chelsea as well as two La Ligas and a Europa League with Atletico.
