Paul Gallen has conceded he is no chance of playing before the opening State of Origin game ahead of a crucial phase in his rehabilitation from a hip injury this week.

The NSW skipper remains a 50/50 proposition for Origin I in Sydney on May 27 as the Blues begin their quest for back-to-back interstate titles for the first time since 2005.

Recovering: Paul Gallen of the Sharks is tackled against the Roosters. Credit:Getty Images

Gallen received a setback last week when his recovery from the injury stalled, causing him to have it reassessed, putting his Origin plans in jeopardy.

If the Cronulla skipper is fit for game one, he won't have played since the Shark's round six NRL clash against Newcastle on April 10, a gap of almost seven weeks.