Defending champion Andy Murray [ Images ] and ATP finals hopefuls Mikhail Youzhny and Fernando Verdasco [ Images ] all made surprise early exits from the Valencia Open on Wednesday.

World number four and top seed Murray fell 6-2, 3-6, 6-2 to Argentine Juan Monaco in the second round, while world number 10 Youzhny pulled out at the start of the day with a back problem.

The Russian was due to play Uruguayan qualifier Pablo Cuevas in his opening match, but had to give his place over to Spaniard Albert Ramos-Vinolas who lost 6-3, 6-4.

Spaniard Verdasco, the third seed and world number seven, was crushed 6-1, 6-3 by Frenchman Gilles Simon.

Youzhny and Verdasco's exits damaged their chances of making the season-ending ATP finals later this month, as they fought for the three remaining berths in London [ Images ].

Rafael Nadal [ Images ], Roger Federer [ Images ], Novak Djokovic [ Images ], Murray and Robin Soderling [ Images ] have qualified so far, the latter is also competing in Valencia.

David Ferrer and Nikolay Davydenko [ Images ] have the chance to push their claims for London in the quarter-finals on Thursday, when second seed Soderling also plays.