Rubens Barrichello has revealed he held talks with McLaren before signing with Williams for 2010.
The Woking based team ultimately signed the Brazilian's 2009 Brawn teammate and reigning world champion Jenson Button to partner Lewis Hamilton this season.
But Barrichello, 37, finished last year's standings in third place, having outpaced Button with identical machinery in the second half of the year.
"They (McLaren) called me a couple of times in November at the Brazilian race, to see if I was available," said Barrichello in Valencia, where on Tuesday he continued to test Williams' new FW32 car.
He said he is sure he was not McLaren's only alternative to Button.
"If they called me, I'm sure they called him (Button) at the same time. I'm sure they were questioning as soon as (Kimi) Raikkonen dropped out of the case, and I'm sure they went on to ask more people, not just us," he added.