American Pete Sampras became the second seed pulling out of the Paris Open after sustaining a back injury on Wednesday.

Hours after Briton Greg Rusedski gave up his hope to defend his title, Sampras told a news conference that he had a spasm during a

Tuesday night game.

The former world No.1 hobbled off court after the 4-6, 6-3, 7-6 (7-4) win over Spain's Francisco Clavet.