Sixth seed Tomas Berdych has been dumped out of the Rogers Cup following a second-round straight-sets defeat to qualifier Donald Young in Montreal.
The 26-year-old American - ranked 79th in the world - stunned his Czech counterpart with a 7-6(5) 6-3 win in one hour and 40 minutes this morning.
Chances of an upset looked unlikely early on when Berdych - a Wimbledon finalist in 2010 - broke his opponent's serve in the fourth game to move 3-1 ahead.
However, Young broke back in the ninth game to trail 5-4, before drawing first blood in the best-of-three clash by edging the tie-break.
Nothing could separate them in the first five games of the second set as Berdych served to restore parity at 3-3, but Young broke to move 4-2 ahead in what proved the pivotal moment of the match as he closed out the win.
Young will face Ernests Gulbis or Lukas Rosol in the third round.