The New Zealand-born player sustained the injury in Ospreys' Celtic League clash against Connacht on April 10 and has been ruled out of the Celtic Cup campaign.

''Sonny won't play another game for us this season,'' Ospreys manager Derwyn Jones told the South Wales Evening Post.

''He suffered a nasty injury in the Connacht game and it is going to take a while to heal properly.

''It's been one bump after another for him.

''He showed at the start of the campaign what an asset he could be - he marked Brian O'Driscoll out of the game when we played Leinster - but since then he has had a run of bad luck which has kept him on the sidelines a lot.

''It must be frustrating for him. He missed Wales's Grand Slam campaign because of injury and had been looking to at least close the season with a flourish. Then this happens.

''But I know he is desperate to do well for the region and I am convinced his best is yet to come in Ospreys colours.''

The 27-year-old has been troubled by neck, shoulder, arm and hand injuries since being brought to Wales by Graham Henry.

''It's too early to say whether he'll be fit for the tour,'' added Jones. ''We'll just have to see how he progresses.''