Wallabies centre Matt Toomua is facing six months on the sidelines after suffering a serious knee injury playing for English club Leicester.
The 33-cap Australian international suffered the knee ligament injury in the Tigers' European Champions Cup pool game against Racing 92 at Welford Road last Sunday.
Inside centre Toomua, who left the field midway through the first half, was set for surgery on Wednesday.
"It is just an accident. Matt stepped and twisted it and his knee has given way," Leicester rugby director Richard Cockerill said.
"He's having surgery today and we're probably looking at six months for recovery from that.
"He is obviously bitterly disappointed. Matt wanted to come in here and make a big impression and we have already seen he is a top-quality player."
Toomua linked up with Leicester earlier this season following his move from the Brumbies and made just two appearances for the Tigers.
The Racing game was his home debut, but Leicester are now look unlikely to see him in competitive action again until the closing weeks of this season.
Toomua featured for the Wallabies during last year's World Cup, making six tournament appearances, including in the final against New Zealand at Twickenham.
The injury continues a tough introduction for European rugby for the 31-Test Wallaby after he was sin-binned for a late tackle during his debut against Glasgow last week.
"We're all disappointed for him, but that's the way it falls sometimes," said Cockerill.
"Matt will be well looked after and we look forward to having him back in the squad when he is fully recovered."
