Robertson did not look in his elements and lost 2-4 to World No.4 Junhui in the first quarterfinal of the 300,000 pound event.
It was Junhui who set the ball rolling with a break of 72 to pocket the first frame 96-4. He went on to win the second frame with a 52-clearance to take the 2-0 lead.
Robertson regrouped his resources quickly and reigned supreme on the green baize with fluent breaks of 86 and 104 in the next two frames to level the issue at 2-2.
Talking about the match, Junhui, who had defeated Robertson in the Shanghai Open recently, said, "I played well today. I took my chances against him and came up with some good clearances.
"The conditions are good here. The tables are not at all sticky. I am looking forward to my semi-final tomorrow," Junhui added.
In the other quarter-final clashes, Robbie Williams beat Anthony McGill 4-0, while Stephen McGuire won a hard-fought battle against Michael White 4-3.
