Nicolai Hojgaard used his Ryder Cup debut to learn from the best golfers in the world.
Now he is upstaging them.
Hojgaard, a 22-year-old Dane regarded as one of the great hopes of the European game, held a share of the first-round lead at the season-ending World Tour Championship after shooting a 5-under 67 at the Earth Course in Dubai on Thursday.
McIlroy made three bogeys in his final seven holes -- one coming after his tee shot at the par-3 13th ended up on the lap of a spectator -- and shot 71. Rahm shot even par after finishing bogey-bogey.
Hojgaard was a rookie and the youngest player at the Ryder Cup won by Europe last month outside Rome. He spent time inside and outside the team room watching how the likes of Rahm and McIlroy operate.
In his two European tour events since golf's biggest show, Hojgaard tied for second at the Nedbank Golf Challenge in South Africa last week and now is leading the $10 million tour finale.
"Just being around those guys, seeing what they do, what do I do different and what do I need to work on, it gave me a lot of confidence going into the end of the season," Hojgaard said. "You want to play with those guys, but you want to beat them too."
Fourth-ranked Viktor Hovland, who won the equivalent event -- the Tour Championship -- on the PGA Tour in August, shot a 69, including making bogey after needing to chip off a wooden bridge at No. 17. He was tied for seventh place, 2 strokes off the lead.
McIlroy has already clinched the Race to Dubai title and been named Europe's No. 1 player for the fifth time, taking away one of the big subplots in a week that also included his decision to resign from the PGA Tour's policy board.
"I just think I've got a lot going on in my life between my golf game, my family and my growing investment portfolio, my involvement in TGL, and I just felt like something had to give," McIlroy told reporters Thursday. "I just didn't feel like I could commit the time and the energy into doing that."
The Associated Press contributed to this report.