The United States' Ben Shelton on Friday became the first top-10 seed to be booted out of the Shanghai Masters, beaten by 83rd-ranked David Goffin in straight sets.
The Belgian underdog beat 22-year-old Shelton, ranked sixth in the world, 6-2, 6-4.
Starting strong, the 34-year-old broke the American's serve in the third and seventh games to take the first set in just over half an hour.
The second was more closely fought, but shortly after play resumed following a rain break, Goffin broke in the ninth game after an unforced error by Shelton.
The American has been recovering from a shoulder injury sustained at the US Open.
However, Goffin has form when it comes to eliminating top players.
In March this year he upset world No 1 Carlos Alcaraz in Miami and last year in Shanghai he knocked out world No 3 Alexander Zverev.