|-7 J Rahm (Spa); -5 K Kitiyama (US), C Kirk (US), C Young (US); -4 A Shenk (US), S Scheffler (US), J Spieth (US), A Rai (Eng), X Schauffele (US), P Cantlay (US), R Fowler (US), K Bradley (US)|
|Selected others: -2 M Fitzpatrick (Eng), D Willett (Eng); -1 V Hovland (Nor), L Donald (Eng), T Hatton (Eng), M Laird (Sco); E S Lowry (Ire); +1 R McIlroy (NI), T Fleetwood (Eng)|
World number one Jon Rahm shot a seven-under-par 65 to take a two-stroke lead after the first round of the Arnold Palmer Invitational at Bay Hill.
The Spaniard made six birdies and an eagle and the only blemish on his scorecard was a bogey at the eighth.
Chris Kirk, who won last week’s Honda Classic, is in a three-way tie for second with fellow Americans Cameron Young and Kurt Kitayama.
Defending champion Scottie Scheffler is one stroke further back on four under.
Rory McIlroy opened with a bogey after finding a greenside bunker and it signalled the start of a see-saw round for the Northern Irishman.
The 33-year-old, ranked third in the world behind Rahm and Scheffler, made three birdies but a double bogey at the sixth and a dropped shot at the 14th – where he again found sand – proved costly as he signed for a one-over 73.
It was a more positive day for Englishman Aaron Rai, who started on the back nine and is well placed alongside Scheffler after a 68.
Jordan Spieth, Xander Schauffele, Patrick Cantlay, Keegan Bradley and the resurgent Rickie Fowler are also in a high-powered group on four under.
They are part of a top-class field that contains 43 of the world’s top-50 players who are competing for a purse of £17m, of which more than £3m will go to the champion.
US Open champion Matt Fitzpatrick and former Masters winner Danny Willett both recovered from double bogeys to finish with two-under 70s.
Fellow Englishmen Tyrrell Hatton and Luke Donald also made encouraging starts to sit one under alongside Scotland’s 2011 Bay Hill winner Martin Laird.