The All Blacks midfielder is expected to turn out for Ponsonby over the next two weeks.
Williams endured another difficult, injury-disrupted season for the Blues which restricted him to three starts – his final appearance against the Hurricanes in Wellington on June 15 coming after a 10-week layoff following knee surgery.
Such a frustrating campaign left him lacking game-time and match fitness ahead of the Rugby Championship and World Cup in Japan.
The 33-year-old therefore appears keen to use the grassroots avenue to continue his comeback.
The New Zealand Herald understands at the end of the Blues' Super Rugby season Williams reached out to former All Blacks, Crusaders and Chiefs halfback Kevin Senio and New Zealand sevens playmaker Rocky Khan, both of whom are involved at Ponsonby, about the chance to play for the proud club.
Williams is tied to the tiny Puni club, situated over the Pukekohe hill in the Counties Manukau catchment, and previously played one match for Bombay in his return from suspension after the British and Irish Lions series in 2017.
As a contracted Counties player, Williams needed clearance to play for Ponsonby.
Now that has been officially approved by Counties and Auckland - his registration with Ponsonby coming before the last round cut off on July 6th - Williams is available for the Ponies' next two matches.
Williams' presence will be a huge boost for Ponsonby, Gallaher Shield champions, but also Auckland club rugby on the whole.
No doubt there will be additional supporters lining the sidelines, clambering to see the 51-test second five-eighth in action this Saturday, provided he is selected, as Ponsonby takes on Grammar Tec at the Orakei Domain.
Next week could be even more significant, with Williams potentially running out at Western Springs as Ponsonby host Eden.
All Blacks great Sir Bryan Williams, a life-long servant of Ponsonby, will be among those smiling at the prospect. The club is also home to Rieko and Akira Ioane, and has produced the most All Blacks of any at the grassroots.
Playing for Ponsonby over the next two weeks should allow Williams to build conditioning, confidence and fitness as he works towards the All Blacks' first test of the year against the Pumas in Buenos Aires on July 21.
While many believe Williams faces an uphill battle to make the World Cup squad, given the faith the All Blacks retain in him the reality is he probably only needs to regain full fitness to make the plane.