Rory McIlroy headed straight to the driving range after shooting a one-under-par 69 in Friday's second round at the BMW Championship in St Louis.
The Masters champion began the tournament with a six-under-par opening round to share the lead, but improved his total score by only one shot on Friday to stand at seven under par.
American golfer JJ Spaun set the early pace at Bellerive Country Club, reaching 11 under at the turn before finishing as the clubhouse leader among early starters on 10 under par.
The BMW Championship is the second event of the PGA Tour's annual FedExCup Playoffs, bringing the world's top professional golfers to the championship course at Bellerive in Town and Country, Missouri.
McIlroy session on the range
"I feel like conditions were pretty similar to yesterday," McIlroy told the Golf Channel after his round on Friday.
"The wind was coming out of a different direction, but still very scorable," McIlroy said. "The greens are soft, maybe the ball's got a little bit more run out on the fairways, but you'll still see guys shooting pretty good scores today."
Despite keeping himself near the top of the leaderboard, McIlroy expressed frustration with his striking off the tee and fairway approach shots compared to his opening round performance.
"I didn't quite hit it as good as I did yesterday, so probably an afternoon on the range for me," he added.
McIlroy suffered his only bogey of the day on the par-five eighth hole after an unexpected mistake, but responded with several key par saves on the inward nine to remain in contention.
"I'm proud of how I just hung in there," McIlroy said. "A lot of good par putts on the back nine, especially. The only bogey I had was with a mistake on the par-five eighth hole, but I made some really good par saves coming in and that sort of kept me in it."
As a six-time major champion who won his first major title at the 2011 US Open, McIlroy has long been a standard-bearer on the PGA Tour, relying on consistent iron play and driving distance.
Atmosphere and leaderboard standings
McIlroy praised the enthusiasm of the Missouri gallery, recalling his previous appearance at the venue during the 2018 PGA Championship.
"They're amazing, that's one of the biggest things I remember from being here in 2018 for the PGA was just how many people showed up and what a great atmosphere it was to play in," McIlroy said.
"Yesterday was amazing for a Thursday," he added. "Today, teeing off at 9:45 on a Friday morning and the people out there were incredible. Looking forward to more of the same over the weekend."
Leaderboard rival Spaun opened his second round in blistering fashion, moving to 11 under par through nine holes. Three bogeys on the back nine checked his progress, but birdies on his remaining holes, including one at the last, secured his lead.
World No 1 Scottie Scheffler also staged an impressive mid-round recovery to keep his championship hopes alive. Scheffler had opened with a two-over-par 72 on Thursday and bogeyed his first hole on Friday morning.
However, Scheffler responded strongly after the turn by carding five birdies on the back nine, elevating his total to three under par to stay well within touching distance of the leaders.
Scheffler, who won the Masters earlier this year, has established himself as the premier player in men's golf through remarkable consistency across PGA Tour events.
Live television coverage of the BMW Championship third round continues on Saturday from 4pm on Sky Sports Golf and 8:30pm on Sky Sports Main Event.
