Towering Polish qualifier Jerzy Janowicz upset Andy Murray 5-7 7-6 (7-4) 6-2 on Thursday to complete the early exit of the elite from the Paris Masters.
Murray, seeded third, missed a match point as he followed second seed Novak Djokovic out the door of the Bercy arena 24 hours after the tepid Serb had been beaten by American Sam Querrey.
World number one Roger Federer and injured number four Rafael Nadal did not play the event, which wraps up the ATP regular season and will decide the last two qualifiers for the eight-man World Tour Finals starting on Monday in London.
Murray had never been beyond the Bercy quarter-finals and looked like having the perfect chance to fix that blemish in his record.
But beanpole Janowicz upset the form book with his huge serve, which produced 22 aces and 51 winners in just under two and a half hours.
The 21-year-old winner scored the biggest win of his career on his second match point and fell to the ground with his hands over his eyes lying on the court in pure joy.
Murray did not want to predict how the exits of himself and Djokovci might affect their showings in London next week.
"Only time will tell really. A lot of the players will have had slightly different run ins to the O2. Obviously me and Novak lost early this week; Roger didn't play, and then I think the rest of the guys are still in here.
"You never know, maybe the guys that go deep here they'll have confidence from having a good tournament. But they may arrive a little bit later and might take a while to get used to the conditions."
Murray's defeat means that the Paris quarter-finals will be the first in four years at a Masters 1000 not to feature at least one of the top four players.
Janowicz had beaten a pair of top 20 opponents this week in number 19 Philipp Kohlschreiber and number 15 Marin Cilic, never facing a break point in those matches.
Murray came out firing against the youngster's huge serve and won the opening set on a break of serve through his opponent's double-fault.
But the challenger came back in the second after going down a break, putting Murray on the back foot from a pair of sloppy forehands to level at 5-5 after the Scot had served for victory while putting a forehand cross-court wide on match point.
As the set went to a tiebreak, Janowicz took more initiative, winning it on a volleyed winner off a weak Murray dropshot.
The Pole seized the match in the final set with two breaks of serve and a 5-1 lead before putting it away two games later.
London qualifier Tomas Berdych, the Czech fifth seed, came back to defeat South African Kevin Anderson 1-6 6-3 6-4 while the luck continued for Gilles Simon as the Frenchman advanced when Japanese opponent Kei Nishikoi withdrew with an ankle injury.
Simon won in the first round against lucky loser Victor Hanescu, who replaced Federer in the draw.