Chelsea's top scorer Alvaro Morata has pulled out from the Spain squad for their final two World Cup qualifiers, with Barcelona midfielder Andres Iniesta and Real Madrid right-back Dani Caraval also due to miss the matches with a variety of fitness problems.
Spain host Albania in Alicante on 6 October before travelling to Israel three days later - with Julen Lopetegui's side needing four points from their final two games to confirm qualification for Russia 2018. La Roja currently lead Group G by three points ahead of Italy.
Morata started Chelsea's 1-0 defeat to Manchester City on Saturday (30 September) but was forced off and replaced by Willian in the 35th minute.
Antonio Conte suggested after the game that the injury was not serious, but the boss predicted that Morata would be unable to go on international duty with Spain.
"It's a muscular problem. I don't think it's serious. He said to me: "Coach I prefer to stop, otherwise I risk having a bad injury," the Chelsea boss said in the press conference following the defeat to City. "I don't know. The doctor in the next few days will check the situation but I don't think he will be available for the national team."
Spain have confirmed that news after subsequent scans underwent in Madrid confirmed that the Chelsea star suffered a "hamstring" injury.
"Alvaro Morata (Chelsea FC) suffers a grade II myofascial injury in the hamstring muscles," Spain confirmed.
"The Spanish squad's medical services received medical reports on Dani Carvajal and Andrés Iniesta from their clubs and carried out an MRI scan on Álvaro Morata at the Sanitas University Hospital of La Moraleja (Madrid), where the diagnosis was confirmed."
Spanish doctors have failed to set a timeframe on the recovery but reports are suggesting that Morata could recover in time for the Blues' trip to Crystal Palace on 14 October. Lopetegui has named Athletic Club Bilbao striker Aritz Aduriz to replace the Chelsea number nine. Diego Costa was overlooked to replace Motata with the new Atletico Madrid striker having not played this season.
Meanwhile, the Spanish national team have confirmed that Barcelona captain Iniesta and Real full-back Dani Carvajal have also withdrawn from Lopetegui's squad due to injury and illness respectively.
Real Sociedad right-back Alvaro Odriozozla and Las Palmas midfielder Jonathan Viera will fill the voids left by the unavailable pair.