The 22-year-old from Northern Ireland had a 16 under score last month at Congressional. He's favored to make it two majors in a row at Royal St. George's. The group tees off at 4:09 a.m. ET on Thursday.
ESPN coverage of the championship begins at 4 a.m. on Thursday.
The world's top-ranked player, England's Luke Donald, is grouped for Thursday and Friday with Ryo Ishikawa and Sergio Garcia. Donald solidified his spot in the rankings with a four-stroke victory this past weekend at the Scottish Open. That group opens play at 4:20 a.m. ET
Among the top Americans, two-time PGA Tour event winner Nick Watney is paired with long-hitters Matteo Manassero and Angel Cabrera at 3:31 a.m. ET while Hunter Mahan plays alongside Retief Goosen and Anders Hansen at 4:31 a.m. ET.
Among the late afternoon (British time) starters are Matt Kuchar, who plays with amateur Bryden Macpherson and Padraig Harrington at 8:21 a.m. ET; Zach Johnson, who is paired with Adam Scott and Justin Rose at 8:32 a.m. ET; and Bubba Watson, who will play with Graeme McDowell and Jason Day at 8:43 a.m. ET.
Information from The Associated Press is included in this report.