Perry completed three rounds at 18-under 192. That's one-stroke lower then he had when he won the Colonial two years ago.
Temperatures at Colonial Country Club peeked at a record high of 97 degrees during the round.
"Every time I hit it, I found some shade to walk under the whole way to my ball," Perry said.
Perry, 44, has had eye problems the last few months. He has had lasik surgery twice on his eyes. He has been relying on his memory -- this is his 16th Colonial -- and his caddy with help reading the greens.
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