They are in Group 2
Rory McIlroy has been beaten 2&1 by Soren Kjeldsen in their first group game at the WGC Dell Technologies World Matchplay.
The Dane got off to a good start in Group 2 by beating the World No 2 in Austin, Texas.
McIlroy was only briefly ahead of Kjeldsen, who won the Irish Open in 2015 and is ranked 68th in the world (the third lowest ranked player in action in Austin this weekend), taking the lead on the fourth hole.
Kjeldsen then retook a one shot lead at the turn, although McIlroy went one up on the 13th before the Dane fought back to beat the Northern Irishman 2&1.
Also in Group 2 with that duo are 26th seed Emiliano Grillo of Argentina and USA's Gary Woodland who is seeded 33rd and ranked 37th.
Woodland won their match 3&2.
McIlroy will face Woodland next, while Kjeldsen and Grillo will go head to head.
Ireland's Shane Lowry, who is in Group 7, will start off against Spain's Sergio Garcia.