The 23-year-old takes over as Britain's sprint king and poses the question to selectors whether they should pick drug-cheat Chambers for next month's World Championships in Berlin.
By their own rules, they have to select only the winner of the Aviva World Trials - and that means Chambers, 31, could be ditched.
He would have to win today's 200m final to ensure his place on the plane.
Williamson said: "I was hoping to go sub-10 but into that wind it was the equivalent - that is now the next step.
"Yet I'm happy to win my first national title - after being the bridesmaid so many times now I'm the bride."
Chambers, who has been talking himself up after a series of B races as he continues to be excluded from the big meetings across Europe, said: "We have both qualified and that's the important part."
But the realisation seemed to hit him like a cold shower immediately after the race in the Alexander Stadium when he said: "I have made the team, hopefully."
Word is that Chambers, who has already been excluded from the sprint relay, has yet to step up his speed work as he bids for the double place of 100m and 200m.
But his performance of 10.22sec on a flat, dull day will not make any impact on Olympic champion Usain Bolt and Tyson Gay - with both recently running 9.77sec.
Chambers was given an evening's rest as the 200m heats were halted after rain fell.
Another worry for Berlin is the form of Christine Ohuruogu, reigning World and Olympic Champion.
She concentrated on the 400m and though she won easily from hurdler Perry Shakes Drayton, she looked short of stamina work. But Christine said: "If I compare my progress to last year, it is pretty much the same."
The big surprise was unknown Charlene Thomas, from Ilkley, beating the outstanding Stephanie Twell in the 1500m. Charlene beamed: "I have booked my seat."
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