Luck birdied his final hole after finding the water and taking bogey at the 17th but with sixteen birdies in his opening 36 holes he has shown a marked improvement on his earlier season PGA Tour form.
Luck is in his rookie season at this level and showed remarkable resilience to save bogey at the 17th, his approach from the drop area after his tee shots finished in the water finishing three feet from the hole and then going onto birdie the last to keep Mickelson, who opened with a round of 60 yesterday, well and truly within striking distance.
Luck played the Nicklaus Tournament Course today and is in fact playing the event's venues in the same rotation as Mickelson.
Adam Hadwin and Steve Marino are another shot back in a share of 3rd while defending champion Jon Rahm is tied for 5th at 12 under and four from Mickelson's lead.
Cameron Davis is 46th, Aaron Baddeley 72nd, Matt Jones is 103rd, John Senden 118th and Rod Pampling even further back.
The cut in the event comes tomorrow after 54 holes after all three venues have been played by the competitors before the event returns to the Stadium Tournament Course for Sunday's final round.
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