Josh Strauss has been ruled out of the Six Nations with a kidney injury while Scotland continue to count the cost of their bruising defeat by France.

The South Africa-born No8 joins the Scotland captain, Greig Laidlaw, on the sidelines for the remainder of the competition after the SRU confirmed he would be out of action for six weeks.

Laidlaw’s participation was ended by an ankle injury that forced him off during the 22-16 defeat in Paris. Earlier this week it was revealed he had suffered ankle ligament damage. Strauss finished the match, in which the flankers John Hardie and John Barclay, the centre Alex Dunbar and the hooker Fraser Brown all came off with head injuries. A scan in Paris revealed the extent of Strauss’s injury.

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An SRU statement read: “After completing the match, he was scanned in Paris. Both the scan, and the player, were reviewed at Murrayfield Hospital back in Scotland, where the full extent of the injury was confirmed. Strauss will now return to Glasgow Warriors for further care.”

The Ireland centre Jared Payne is out with a similar kidney injury and while Strauss is expected to recover more quickly, his absence is a major blow for Scotland’s coach, Vern Cotter. Strauss, who made his debut at the 2015 World Cup, having become eligible on the eve of Scotland’s first match in the tournament, was among their standout performers against a huge France pack last Sunday. Ryan Wilson, who missed out in Paris with an elbow infection but started the opening day victory over Ireland at blindside flanker, is an option at No8 against Wales next Saturday, as is the uncapped, South Africa-born Cornell du Preez.

Cotter refused to blame Scotland’s litany of injuries for their failure to claim a first away win against France for 18 years but Laidlaw in particular was a significant loss. Ali Price is expected to replace him against Wales, who will hope to have Taulupe Faletau back in the starting XV after the No8 was named in Bath’s starting lineup to face Harlequins on Saturday.

Wales’s match in Tonga in June will be relocated to another country owing to delays in the redevelopment of the national stadium in Nuku’alofa.

The WRU chairman, Gareth Davies, said: “Everyone involved in the planning for this tour wanted the game to be hosted in Tonga and this is the reason we have delayed before confirming the fixture. The Tonga Rugby Union should be commended for their efforts in relation to the redevelopment of their national stadium but unfortunately time has proved to be against us.”

Willie le Roux is set to make his Wasps debut at Sale on Sunday after the South Africa full-back was named on the bench by Dai Young.