JUST days after producing his best performance in a Scotland shirt, Josh Strauss, the back row, has been ruled out of the rest of the RBS Six Nations Championship with an injury serious enough that it might also mean he has played his last game for Glasgow Warriors.

The South African-born No.8 was outstanding in Scotland's defeat in Paris a week ago but when the medical staff examined the damage from a bang on the side he sustained during the game they quickly realised injury had gone deep enough to have affected the kidney too.

He was scanned in Paris and then again when he got back to Scotland, with both confirming the kidney damage. He does not seem to need surgery, but the next review is not for another six weeks, taking him to the start of April.

If that does not clear him for a return to action, he would be running out of time to play again before the season ends – and Glasgow Warriors have already announced that he is among those leaving the club in the summer.

His injury comes as the latest blow to Vern Cotter, the Scotland coach, as he prepares the team to take on Wales next week, with Greig Laidlaw, his captain, goalkicker and main tactician, having already been ruled out with ankle ligament damage.

Now he has also lost his main ball carrier, one of those up front who matched the French physicality last weekend with 16 carries – the most of any Scottish player – making 47 metres – the beaten only by Sean Maitland and Stuart Hogg running back kicks.

Ryan Wilson, who missed the Paris game with an elbow infection is likely to be recalled and replace Strauss at No.8, but he is nearly two stone lighter and a very a different style of player.

It looks as though John Barclay should come through his head injury checks, to slot back in at flanker, but they will need an all-rounder on the bench. John Hardie is also having a head injury checked over and if he fails – he looked out for the count when he was helped from the field – it might mean a debut cap for Cornell du Preez, another South African who qualifies on residency, or a recall for Rob Harley.

For Strauss, the irony was that finally, on his 11th cap for his adopted country, he was starting to produce the kind of form he has been producing regularly for Glasgow Warriors, only to pick up this injury.