|Arnold Palmer Invitational leaderboard|
|-6 Morgan Hoffmann (US), -5 Ken Duke (US), Ian Poulter (Eng), Kevin Na (US), Jason Kokrak (US), John Peterson (US), -4 Henrik Stenson (Swe), Adam Scott (Aus), Padraig Harrington (Ire), Brandt Snedeker (US), Martin Laird (Sco)|
Morgan Hoffmann secured his first ever lead at the end of a day's play on the PGA Tour just hours after learning of his grandmother's death.
The American, 25, was told his 97-year-old grandmother had passed away in the early hours of Thursday morning but steeled himself to shoot a six-under 66 at the Arnold Palmer Invitational.
That was enough for a one-shot lead at Bay Hill. England's Ian Poulter was among five players tied for second.
Rory McIlroy shot a 70 to lie 32nd.
Hoffmann carded four birdies but the high point came when he holed a bunker shot for eagle on the par-five sixth.
The world number 137 hopes to get to a memorial service for his late grandmother in Fort Lauderdale on Saturday, when the third round is due to be played.
He plans to make the short trip in the single-engine plane that he pilots.
"Mentally, I'm in kind of a weird state right now," Hoffmann said. "My grandma passed away this morning, so I'm just pretty chilled out there and loving life right now.
"I just wish my family the best at home. My whole family texted me and said, 'Nanny is playing golf with pop up there', which was pretty cool."
Behind Hoffmann, there was a bogey-free round from Englishman Poulter, who signed for 67 after three birdies and an eagle at the 16th.
Poulter was joined on five under by American quartet Jason Kokrak, Kevin Na, Ken Duke and John Peterson.
Shot of the day went to Brandt Snedeker, who enjoyed an amazing slice of fortune on his way to a 68.
The American's approach to the 18th twice bounced off the rocks on the edge of a water hazard and on to the green, within feet of the hole.
"I've never seen that happen before," Snedeker said. "I've seen some crazy bounces there before, but none like that."
World number one McIlroy is in touch at two under, although he would have signed for better had his approach to the 16th not come up short and rolled into the water.
That was the only green McIlroy failed to hit in regulation - equalling his career best - and led to a bogey six.
"I feel OK," said McIlroy, who has yet to break 70 on the PGA Tour in 2015. "I saw a lot of positives out there and was just trying to stay as patient as possible."