Toomua in race against time

Sydney - Australia centre Matt Toomua risks being ruled out of the rest of the Rugby Championship as he struggles to recover from concussion.

Toomua took a knock to the head in the first Test against New Zealand in Sydney which was his fourth concussion in the last three years. He won't be available for the upcoming Tests against South Africa and Argentina and could also miss the return Tests in October, reports AAP.

Toomua previously suffered concussion in two successive Test matches in 2014 which left him on the sidelines for more than a month. With Matt Giteau and Rob Horne already ruled out with a broken ankle and shoulder injury respectively, Wallabies coach Michael Cheika could be forced to keep Bernard Foley at inside centre.