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Petrov, 37, played the second half of an 8-0 friendly win over Austrian club GAK Graz.
The former Bulgaria international was diagnosed with acute leukaemia in March 2012 before retiring the following year.
The midfielder has been training with Villa, now in the Championship, during pre-season.
Petrov has made over 180 league appearances for the club since joining from Celtic in 2006.
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Jordan Ayew, Rudy Gestede and Joe Bennett scored braces in the win, while Micah Richards and Libor Kozak were also on the scoresheet.