The Northern Irishman arrives at Quail Hollow as the man to beat, having won the Masters earlier this season to complete the career Grand Slam and seemingly take the major pressure off his shoulders.
This is also a course he has won four times at, but there was little for him to smile about during a frustrating opening round as he shot a first round of 74, struggling off the tee all day.
Scottie Scheffler is playing alongside McIlroy for the first two rounds and the world number one was five shots better than his playing partner, shooting two-under to keep himself firmly in the mix.
European Ryder Cup captain Luke Donald was the surprise story, shooting four-under par, and he sits a shot better than the likes of Matt Fitzpatrick and Robert MacIntyre.
When is Rory McIlroy playing at the PGA Championship?
McIlroy will be back alongside Scheffler and defending PGA Tour Championship winner Schauffele on Friday.
The trio are scheduled to tee off at 6:47pm BST.
PGA Championship tee times
Selected second-round groupings (all times BST unless stated)
*group starting on hole 10
12:27pm: *Lucas Glover, Max Homa, Joaquin Niemann
12:38pm: *Tyrrell Hatton, Will Zalatoris, Adam Scott
12:49pm: *Justin Thomas, Dustin Johnson, Collin Morikawa
1pm: *Jordan Spieth, Patrick Reed, Ludvig Åberg
1:11pm: *Hideki Matsuyama, Wyndham Clark, Tom Kim
1:22pm: *Bryson DeChambeau, Viktor Hovland, Gary Woodland
1:33pm: *Sergio Garia, Daniel Berger, Russell Henley
1:44pm: *Justin Rose, Cameron Smith, Brian Harman
5:25pm: *Luke Donald, Padraig Harrington, Martin Kaymer
6:03pm: Brooks Koepka, Rickie Fowler, Shane Lowry
6:14pm: Phil Mickelson, Tommy Fleetwood, Jason Day
6:25pm: Jon Rahm, Patrick Cantlay, Matt Fitzpatrick
6:36pm: Corey Conners, Min Woo Lee, Rasmus Hojgaard
7:26pm: *Greg Koch, Marco Penge, Ryan Gerard
Star duo: McIlroy will play alongside Scottie Scheffler for the first two rounds, as well as Xander Schauffele
Getty Images
How to watch the PGA Championship
TV channel: In the UK, live coverage of the 2025 PGA Championship is provided by Sky Sports. Daily broadcasts begin at midday for the first two rounds on Sky Sports Main Event and Sky Sports Golf, moving to 1pm on Sky Sports Golf on Saturday and Sunday.
Sky Sports Main Event joins the coverage from 5pm on Saturday and 7pm on Sunday.
Live stream: Sky Sports subscribers can also watch the action live online via the Sky Go app.
PGA Championship prize money
The exact prize pool for the 2025 PGA Championship has yet to be officially disclosed, but last year Schauffele pocketed a cool $3.3million at Valhalla from a total pot of over $18m after beating Bryson DeChambeau by one shot.
Odds via Betfair (subject to change).