Sebastien Grosjean shattered world number one Lleyton Hewitt's bid for an unprecedented fourth consecutive Stella Artois title at Queen's Club today.
The enigmatic Frenchman roared to a 6-3 6-4 quarter-final victory over the Wimbledon champion to move into the semi-finals.
Andre Agassi, meanwhile, regained his place on top of the world after his 6-4 7-5 quarter-final win over Belgium's Xavier Malisse.
Victory means the 33-year-old American reclaims the world number one ranking following Hewitt's defeat. Agassi followed up his thrashing of Richard Krajicek last night with another dominant performance against last year's Wimbledon semi-finalist.
An early break in the first set proved enough for him to gain the upper-hand although Agassi did suffer the rare embarrassment of watching four consecutive Malisse aces fly past him in the ninth game of the second set.
The American used his experience to grab the second break when it mattered and served out to love to move into the last four.
Agassi said: "You're always going to have a lot of great tennis when you're playing someone like Xavier and I just took my chances.
"It's great to play in this tournament and I wish I'd been here more often through the years. The courts are beautiful and it's a great opportunity to play against some of the world's best grass-court players."
Earlier, Grosjean's delightful range of back-court shots proved too much for Hewitt but only after an enthralling one hour 28 minute battle.
Grosjean, who reached the Wimbledon fourth round five years ago, hit back from being broken in the third game of the match and levelled immediately.
He grabbed the crucial second break in the sixth game and served out to draw first blood against Hewitt, who had struggled desperately to come through his previous round against Belgium's Dick Norman yesterday.
Hewitt was flopping far too many volleys into the net and Grosjean seized his opportunity to grab a second-set break in the fifth game.
But it looked like he might rue his failure to convert two points for a double break at 4-2 when the tenacious Hewitt came straight back to level the match.
But a wild forehand into the tramlines gave Grosjean a break back and the chance to serve for the match. A poor second serve caught out Hewitt who flopped another forehand into the net and the Australian's 17-match reign as Queen's Club champion was over.