RORY McIlroy found the thin air of Mexico City to his liking as he enjoyed a solid start on his return to competitive action in the WGC-Mexico Championship.
McIlroy, who has played just once in 2017 due to a rib injury which saw him push through the pain barrier before losing to Graeme Storm in a play-off for the South African Open in January, signed for a three-under par round of 68, the highlight being a 30-foot eagle putt on the par-five sixth hole, his 15th.
He was in a group of seven players one shot behind another group of six players who shared the lead on four-under par. That group was made up of English duo Lee Westwood and Ross Fisher; Spain's Jon Rahm and American trio Phil Mickelson, Jimmy Walker and Ryan Moore; while alongside McIlroy on three-under were European challengers Thomas Pieters, Chris Wood and Sergio Garcia; American duo Pat Perez and Matt Kuchar and South American Fabrizio Zanotti
McIlroy arrived at Chapultepec Golf Club knowing that he could reclaim top spot in the world rankings for the first time since August 2015 by winning his third World Golf Championship title, as long as current number one Dustin Johnson finished joint fourth or worse.
And the Holywood man was in the ideal place to keep an eye on Johnson's progress over the first two days after being paired with the US Open champion and Japan's Hideki Matsuyama.
Starting on the back nine of a course which reaches a maximum of 7,800 feet above sea level, McIlroy holed from 15 feet for birdie on the par-five 11th and added seven pars in succession to reach the turn in 35.
The four-time major winner then drove into a greenside bunker on the short par-four first hole and got up and down for birdie to reach two-under par, while Johnson ran up a double bogey after hitting his tee shot out of bounds.
McIlroy dropped his first shot of the day by three-putting the fifth from long range, but produced the ideal response by holing from 30 feet for an eagle on the par-five sixth to move to three-under par
There was not such good news for European number one Henrik Stenson, the Open champion withdrawing with a reported stomach virus midway through the opening round.
McIlroy was also reported to be under the weather but still signed for a three-under-par 68.
"The rib is fine, it's great actually," McIlroy said in an interview broadcast on Sky Sports. "How I've responded the last couple of weeks, ramping up the practice and then playing my first full competitive round today, I didn't feel it at all so all positive in that regard.
"I probably could have played the Honda (Classic) last week but I wasn't going to know how my body was going to react playing four days in a row.
"I'm taking next week off to see how everything reacts and responds so it was the logical place to come back. I stayed patient and the week longer will definitely pay off."
