The pair are one ahead of a group of five players but defending champion, Jason Day, is just two off the lead after he too finished strongly with a closing nine of 32 for a round of 68 to share 8th place with amongst others, his fellow Queenslander John Senden.
Matt Jones is the next best of the Australians at 1 under 70 while Curtis Luck recorded a round of 71.
McIlroy has great memories of the Quail Hollow Club despite its rather significant alterations since his first PGA Tour win there in 2010.
He would win there again in 2015 along with four other top tens in the event in addition to the wins and that record, along with his fine form to date in 2019, had him as the favourite for the title heading into this week and he has made the near perfect start.
After making the turn at even par, McIlroy birdied the 10th, 11th, 14th, 15th and 16th and missed a very makeable birdie opportunity at the last which would have given him the outright lead.
Dahmen has yet to win on the PGA Tour although he did finish runner-up at last year’s John Deere Classic and has produced several good results in 2019. He finished 16th in this event after missing the cut on debut in 2017.
Day, along with partner Adam Scott, missed the cut last week in New Orleans but given the format of that event not a lot could be read into it and so it has turned out. His last start in an individual PGA Tour event was when finishing 5th at The Masters and, as the defending champion in this event, he is already indicating he will be a force to be reckoned with by Sunday.
Senden has generally battled since his return to tournament golf following time away from the game to address a life-threatening illness to his son Jacob. He has often played well at Quail Hollow Club and his start here is encouraging.
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