Asier Illarramendi has admitted that 'it will be difficult' for him to claim a spot in the Spain squad for the 2018 World Cup.

Illarramendi capped just his second La Roja appearance with a goal in Monday night's 1-0 win over Israel.

The Real Sociedad midfielder was one of a number of fringe players given the chance to impress after Spain had booked their spot in next summer's World Cup over the weekend.

The 27-year-old has vowed to "fight" for a place in Julen Lopetegui's squad, but has accepted that he might miss out due to the midfield options available.

"I'm very happy to play and do my bit, and my goal was ultimately needed for the win, which was important. World Cup? It'll be difficult for me to go to Russia. Everyone here has a chance [of making the squad] and we'll fight [to be there]," Illarramendi told reporters.

Illarramendi returned to Sociedad in 2015 after spending two seasons at Real Madrid.