English is among the four languages Roger Federer speaks fluently. He is conversational in another four.
But even the multi-lingual Swiss superstar might well need a translator to make sense of John Millman's take on his advice that other players should give more of themselves to the world's tennis media.
Millman bowed out in the second round of the Australian Open to combustible Bosnian Damir Dzumhur on Wednesday and later expressed regret at not demanding a Hawk-Eye review midway through a rally at set point.
Dzumhur went on to win the point and the third set before careering away to triumph 7-5 3-6 6-4 6-1 and set up a third-round clash with world No.1 Rafael Nadal.
"It's all well and good saying you should use Hawk-Eye or whatever but when you're in the middle of the point it's a bit Russian roulette," said the 28-year-old Millman.
"You could stop the point and then it catches a tiny bit of (the line) - but I thought it felt long.
"I might not have had the swingers to make the call.
"Roger said we should not be so (robotic) and that's how I talk."
How the colloquialism "swingers" would translate into Swiss German is anyone's guess.
Dzumhur lost his composure midway through the second set, allowing Millman to string together six straight games.
But for much of the remainder of the match it was the Bosnian 28th seed who held sway.
"It's tricky with him," said Millman.
"If you watch him play a bit, that's what he does.
"Sometimes he loses focus but his game is still there."
Dzumhur also made regular and successful use of his drop shot to catch the Australian off-guard.
"I don't know what the stats are but I reckon last year he probably played the most drop shots on tour by a fair way," said Millman, who played the Open on an injury-protected ranking.
"He's got great hands.
"If you don't read it and you're a bit wrong-footed, there's not a lot you can do to be honest.
"You can just watch it float over the net."