Casey put in a solid performance to keep well in touch with the leaders
England's Paul Casey is one shot off the lead after a first-round 66 in the weather-interrupted Houston Open.
Briny Baird and Nicholas Thompson are tied for the lead in the clubhouse on seven under par.
Casey is joined on six under by Jason Nitties, Tommy Armour III, Scott Piercy and Darren Points.
Play at the Masters warm-up event was postponed because of high winds and many of the 72-player field will have to resume their first rounds on Friday.
England's Lee Westwood was heading the field after firing a four-under 32 on the front nine but dropped one shot to fall off the pace.
Justin Rose was also well placed after ending his first-round four under.
The tournament at the Redstone Golf Club is the last event before the Masters at Augusta later this month.
Although world number one Tiger Woods is absent, eight of the world's top 10 golfers including American Phil Mickelson (ranked second), Spaniard Sergio Garcia (third), Australian Geoff Ogilvy (fourth) and Irishman Padraig Harrington (fifth) are in action.