The son of longtime PGA Tour player Jay Haas broke 70 for the first time in five Augusta National appearances. The 31-year-old American started the tournament with a bogey, but bounced back to knock in six birdies on a warm, sunny day when only three other players got into the 60s.
The last two Masters winners, defending champion Adam Scott of Australia and 2012 winner Bubba Watson of the U.S., were both at 69. They were joined by South Africa's Louis Oosthuizen, the 2010 British Open champ who lost to Watson in a playoff two years ago.
Three-time winner Phil Mickelson struggled to a 76. Iowans Zach Johnson and Michael McCoy both finished with a 6-over 78.
Copyright 2016 Nexstar Broadcasting, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.