Highlanders wing Waisake Naholo is set to be sidelined for up to six weeks with a knee injury.

Naholo suffered the injury at Highlanders training on Monday.

The 27-year-old underwent an MRI scan, which revealed a grade two MCL injury.

The Highlanders are already without All Blacks scrumhalf Aaron Smith, who has been sidelined for four to six weeks with an ankle injury.

Photo: Joe Allison/Photosport