Alex Noren put himself in a strong position against Thongchai Jaidee on day one of the WGC - Dell Technologies Match Play at Austin Country Club.
In a Group 8 clash between two serial winners on the European Tour, the Swede moved two up at the turn as he searches for a first top ten of 2017 after four wins last season.
Group 8 was made up entirely of European Tour Members and Bernd Wiesberger had opened up a slender one up advantage over Francesco Molinari.
Noren holed a 19-footer for birdie on the first and was quickly two up as Jaidee bogeyed the next. A trio of pars followed from both men but a bogey from Noren on the next cut the gap.
It was a scrappy affair and back-to-back bogeys from Jaidee put Noren in command before a double-bogey on the next cut the gap again.
Wiesberger birdied the first and fourth and with Molinari dropping a shot on the third, he was quickly three up. Molinari then won three in a row from the fifth before bogeying the eighth.
Tommy Fleetwood needed just a single birdie in his first six holes to go one up over Zach Johnson in Group 16, where Matt Kuchar was also one up over Brendan Steele after eight holes.
Martin Kaymer was all square after five holes against Jimmy Walker while in the other Group 1 match, World Number One Dustin Johnson was three up after five against fellow American Webb Simpson.
In Group 9, Patrick Reed was one up through ten holes against Jason Dufner, while Brooks Koepka led Kevin Kisner by three holes at the turn.
