British number one Cameron Norrie advanced to the semi-finals of the Diriyah Tennis Cup after claiming two impressive wins over Nick Kyrgios and Stefanos Tsitsipas on Thursday.
After getting the better of the Wimbledon finalist 10-6 10-6 in the Saudi Arabian heat, Norrie followed up his first-round success with a straight sets win over the Greek world number four.
Norrie needed just the one break in the first set against Tsitsipas to put himself in the ascendancy, although he squandered three set points before making it fourth time lucky for a one-set lead.
The Wimbledon semi-finalist quickly went a set and a break up before Tsitsipas threatened a comeback, but Norrie held firm to progress to the final four.
Wawrinka came back from a set down to claim a 6-7 6-2 10-6 win over Andrey Rublev, who now drops into the doubles event with the other players to have been knocked out of the singles competition.
The semi-finals of both the singles and doubles events will take place on Friday before Saturday's finals.