|Wells Fargo Championship first-round leaderboard|
|-7 P Mickelson (US); -5 KH Lee (Kor), K Bradley (US); -4 P Malnati (US), T Fleetwood (Eng), L List (US), G Woodland (US), K Mitchell (US), K Stanley (US)|
|Selected others: -2 J Thomas (US), M Wallace (Eng); -1 B DeChambeau (US), (US), R Knox (Sco); Level S Lowry (Ire); +1 R McIlroy (NI), I Poulter (Eng), L Donald, F Molinari (Ita): Full leaderboard|
Rory McIlroy's one-over-par 72 left him eight behind leader Phil Mickelson after round one of the Wells Fargo Championship.
Northern Irishman McIlroy, who took his first PGA Tour win in the event in 2010 and triumphed again in 2015, managed only two birdies - both early on.
Dropped shots at the 11th and 17th left him sharing 73rd place and needing an improvement on Friday to make the cut.
Open champion Shane Lowry and fellow Irishman Seamus Power shot 71.
McIlroy, 32, has dropped to 15th in the world rankings - his lowest position since 2009 - and 51st in the FedEx Cup standings.
Mickelson, now combining his PGA Tour commitments with the Champions Tour after turning 50 last year, hit five birdies in six holes on his first nine and maintained his momentum as he carded a 64.
The five-time major winner's most recent PGA Tour triumph came in the AT&T Pebble Beach Pro-Am in February 2019.
Mickelson is two shots ahead of fellow American Keegan Bradley and South Korea's Kyoung Hoon Lee, with England's Tommy Fleetwood and American former US Open champion Gary Woodland in a group three off the pace.
Meanwhile, Darren Clarke made an impressive start in the Regions Tradition Champions Tour major event in Alabama as a six-under 66 gave him a one-shot lead.
Clarke, who opened his Champions Tour wins account by triumphing in Florida and Hawaii in November and January, leads Canada's Stephen Ames and American Jerry Kelly by one shot.
"Majors are majors, it doesn't make any difference which tour they're on. You want to play well," said 2011 Open champion Clarke.
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