Sergio Perez has hit back at "those who still doubt", saying money may buy a race-seat but "never" the results.
Speaking at last weekend's Autosport International, Paul di Resta revealed that he had held talks with McLaren about a race-seat for this year's Championship.
However, instead of signing the Scot, McLaren opted to give the drive to TelMex-backed Perez. Di Resta hinted that it was the money that secured the job for the Mexican driver.
"There's a commercial side and money's tight," said the Force India driver. "Perez has some good backing."
Perez has hit back saying his results, which included three podium finishes with Sauber last season, speak for themselves.
"The money can buy you a seat but never the results," the 22-year-old wrote on Twitter.
"Say that to those who still doubt."