An Australian born and raised, Johnson qualified for Scotland on residency grounds last October and he started against Ireland during the Six Nations when he scored a try in the 22-13 Murrayfield loss. Facing him that day were Bundee Aki and Chris Farrell.

Aki is a certainty to start at inside-centre again this weekend. The question is whether the equally abrasive Farrell or the silkier skills of Garry Ringrose will be paired alongside him.

“They are such a physical team,” he explained on Thursday morning, Japanese time, at the team's Tokyo hotel. “A lot of their work comes off (Conor) Murray and (Jonathan) Sexton sort of orchestrates stuff from behind so we are expecting a hugely physical encounter.

But that doesn't mean they don't have the flair out wide to break you on the edges. As I said, it might be weather dependent. That might dictate the terms of play but definitely we are expecting that physicality this weekend.

It's that physicality that Ireland brought to bear in this pair's meeting last spring that still sticks in Johnson's mind though he is quick to add that Joe Schmidt's side offer a far more varied threat that just brute force in this Pool A encounter.

“A lot of their work comes off (Conor) Murray and (Jonathan) Sexton sort of orchestrates stuff from behind so we are expecting a hugely physical encounter but that doesn't mean they don't have the flair out wide to break you on the edges.”

The weather may well dictate how the game is played and, in the choice between Ringrose and Farrell among others, who plays in it. Japan may be a new battle ground for these old rivals but inclement conditions won't be anything new for either of them.

“Their kicking game is going to be a huge strength for them, especially with the weather if it is going to be wet,” said Johnson. “So we need to put as much pressure on their half-back pairing. Murray and Sexton are world-class so we will deal with the threats that are put in front of us.”