Riu’s best result this year was 38th in Singapore in May.
He has never won on the European Tour. On the other hand, Thongchai won the Nordea Masters last month in Sweden.
“My golf game is really very consistent right now,” Thongchai said. “Driver not too good today (but) the putting gives me a lot of chances.”
Stadler won the Phoenix Open in February and was tied for eighth at the Masters in April.
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