Chelsea striker Diego Costa has been ruled out of Spain's matches against Macedonia and England through injury, the Spanish football federation said on Thursday.

Costa had been struggling to shake off a groin injury he suffered in Chelsea's 5-0 Premier League win over Everton on Saturday and immediately underwent medical tests when he met up with the Spain squad.

Spain coach Julen Lopetegui had said that the Brazil-born forward's recovery had been disappointing, and the team later confirmed on their Twitter account that Costa had left the squad and been replaced by Celta Vigo forward Iago Aspas.

Costa, 28, has scored nine league goals in a stunning start to the season for Chelsea and his injury will be a source of concern for the London club's manager Antonio Conte, who has overseen a run of five straight league wins.

Spain face Macedonia in a World Cup qualifier on Saturday before playing England in a friendly at Wembley on Tuesday.

Lopetegui's side are top of qualifying Group G, level on seven points with Italy after three matches.