Lynn was battling with McLaren protege Stoffel Vandoorne and Rapax driver Sirotkin into the first chicane, when he attempted a move on the inside.
He misjudged the braking zone and collided with the helpless Sirotkin, leaving both of them with race-ending damage.
DAMS driver Lynn was handed a five-place grid penalty for the collision but will start from the pitlane as he cannot serve the full demotion having only been 21st on the 25-car grid.
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Lynn accepted full responsibility for the incident.
"Obviously it was my fault," he told AUTOSPORT.
"It's a real shame because obviously I just passed Stoffel.
"The problem was I think it was the first time I arrived with DRS on the pit straight and I braked too late and didn't make the corner.
"Unfortunately Sergey was right in the middle of the corner and couldn't avoid the contact which was a shame, because it ended what was a good race for me and obviously took him out, which isn't fair.
"Luckily the only thing I've got is a bruised ego and I live to fight another day."
Lynn was in contention for the race win at the time, running ahead of eventual victor Alexander Rossi after the frontrunners had pitted.
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Rossi wins after Lynn crashes out
10/10/2015 AT 15:37