It is congested atop the WGC-Mexico Championship standings with Phil Mickelson among the leaders as Rory McIlroy returned to golf in style.
Mickelson, Ross Fisher, Jimmy Walker, Jon Rahm, Lee Westwood and Ryan Moore are a shot clear after the first round on Thursday.
The six players carded four-under-par 67s at the co-sanctioned PGA and European Tour event at Club de Golf Chapultepec in Naucalpan.
Westwood was six under approaching the end of play before the Englishman closed out his round with back-to-back bogeys, while Fisher and Rahm faired best with only one dropped shot apiece.
He was in the sand.-- PGA TOUR (@PGATOUR) March 3, 2017
He was under a tree.
He's on top of the leaderboard.
Phil Mickelson takes us through a fun round. pic.twitter.com/r8oHpBcspM
Former world number one McIlroy is a stroke adrift heading into the second round of the first of four annual World Golf Championships.
Playing competitively for the first time since mid-January because of a rib injury, McIlroy fired a first-round 68.
-- PGA TOUR (@PGATOUR) March 2, 2017
McIlroy had an eagle, two birdies and a bogey to kick-off proceedings and be alongside Matt Kuchar, Sergio Garcia, Thomas Pieters, Fabrizio Zanotti, Chris Wood and Pat Perez.
Justin Thomas and Rickie Fowler, both already winners on the PGA Tour this year, are also in contention at two under.
World number one Dustin Johnson is one under after a shaky day on the greens.
Johnson holed three bogeys and a double bogey, with Martin Kaymer and Jason Dufner also three shots off the pace.
Two-time major champion Jordan Spieth posted a 71, while reigning Open championship winner Henrik Stenson withdrew due to a stomach virus.