Morgan may have come through the qualifying rounds but he has had a useful season, finishing runner-up to Ronnie O'Sullivan at the Asian Classic last autumn, and was expected to prove a tough opponent. And the world No 49 from Essex duly refused to be brushed aside, wiping out his 5-3 overnight deficit to level at 7-7 before going ahead for the first time in the match at 8-7 thanks to a break of 72.
Morgan also had chances to win the next frame but missed a vital blue, and Robidoux punished him with a break of 58 to get on level terms. The world No 14 then clinched victory by taking the next two frames to book a meeting with Peter Ebdon's conqueror, Stefan Mazrocis.
"I had almost forgotten when I won my last match here," Robidoux said afterwards. "Was it before or after the war?"
Robidoux is enjoying his best season since turning professional in 1988. He reached the German Open final last December and is one of a handful of players chasing a place in the top eight for next season.
Jimmy White, the world No 21, began his campaign with a 5-1 lead over Anthony Hamilton in the morning session, despite a fourth frame that lasted almost 40 minutes. From 51-8 down, White took the frame 68-51.