Justin Rose returned to the top of the world rankings on Monday despite having the week off.
The Englishman has been involved in a see-saw battle for the World No 1 ranking with American Brooks Koepka over the past few months, with two regularly taking turns at the top.
Because of the vagaries of the world rankings system, even sitting on the couch with your feet up could result in a move up the list if your closest rival doesn’t have a good week on the course.
This was the case after the Sentry Tournament of Champions on Sunday, where Koepka closed with a 69 to finish 24th – not a bad result, but also not good enough to prevent the top spot from changing hands once again.
Koepka would have needed to finish tied-eighth or better at Kapalua to remain World No 1.
Rose held the top spot for four weeks across three separate spells during 2018, while Koepka had been World No 1 for six weeks up until Monday, having also topped the rankings on two other occasions last year.
Justin Thomas, Dustin Johnson and Bryson DeChambeau occupy the next three places in the standings, with Xander Schauffele moving to a career-high of world No 6 after his impressive come-from-behind win in Hawaii.
Jon Rahm, Rory McIlroy, Francesco Molinari and Tony Finau complete the top 10, with Tiger Woods dropping one spot to 14th.
The American sits atop the leaderboard despite a mixed third round on Saturday.
The Englishman saw a commanding lead cut after a stuttering back nine.
Brooks Koepka made a not-so-subtle dig at Bryson DeChambeau’s “anthill” moment from the first round in Memphis.
The tournament marked the resumption of the tour.
Horsfield fired an eagle and seven birdies in a second round of 63 at the Forest of Arden to share the halfway lead with Sebastian Garcia Rodriguez.
Koepka carded a superb 62 to take a two-stroke lead after the opening day.
A change in date from August to May last year placed the tournament second in line behind the Masters, in calendar terms at least.
The four-time major winner shot 62 in his opening round.
The Northern Irishman needs to win to reclaim the world number one spot from Jon Rahm.