All Blacks rookie Steven Luatua faces a race against time to be available for the opening round of the Rugby Championship.

Luatua picked up a shoulder injury in the Blues’ 34-13 loss to the Cheetahs in Bloemfontein last weekend.

Blues coach Sir John Kirwan says the injury is “not real, real bad” but the loose forward is expected to be sidelined for around four weeks.

“He just needs to rebuild it again,” Kirwan said.

“We don’t think there’s any big damage in there, but there’s nothing we can do about it.”

The All Blacks’ first match of the four-nation tournament is against Australia in Sydney on August 17.

Luatua, 22, gained his debut cap coming off the bench in the third and final Test against France in New Plymouth in June.