Boris Becker called Nick Kyrgios a "rat". Kyrgios said Becker was a "doughnut".
After three months of next to no play because of coronavirus and in the week Wimbledon should have been starting, everyone is perhaps just getting a bit tetchy in the tennis world.
It showed when Becker and Kyrgios engaged in a war of words on Twitter on Tuesday morning, with Becker apparently taking offence at Kyrgios' criticism of Alexander Zverev.
Earlier this week, Kyrgios said world number seven Zverev was "selfish" after a video emerged of Becker's fellow German apparently partying despite saying he was self-isolating having been in close contact with several infected players.