Tony Finau charged into a three-shot lead at the WGC-HSBC Champions as Rory McIlroy tumbled further down the leaderboard courtesy of a nightmare front nine in Shanghai.

Finau was two behind American Ryder Cup teammate Patrick Reed overnight, but moved into pole position by reaching 11-under with a 67, as the first-round leader carded a level-par 72.

Reed was joined at eight under by two Englishmen, defending champion Justin Rose (67) and Tommy Fleetwood (68), while Xander Schauffele shot 71 to be a stroke further back. Half of Finau's eight birdies on Friday came on the four par-fives at Sheshan International GC.

After moving to five-under for the day through 10, he double-bogeyed the 11th before dropping a further shot at 13, but recovered strongly to pick up shots on three of the last five holes.

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Reed had been bogey-free in his opening 64. In round two, though, he followed gains at the second and third with dropped shots on the fifth, sixth and 14th. A birdie at 16 at least ensured he got back to even for the day.

That was a significantly better effort than Mcllroy, who was four over after two holes when he found water twice on the second on his way to a triple-bogey eight.

The four-time major champion also made a seven on the eighth hole and turned in 42 to be six over for his round and the tournament. A one-under back nine left McIlroy five over and 16 shots off the pace.

Ryder Cup hero Francesco Molinari is even further back at seven over, while the world's top two, Brooks Koepka and Dustin Johnson, are also well back at two and three over, respectively.