New Spain boss Julen Lopetegui expects his players to be able to meet any challenge set in front of them, urging them to "add more strings to their bow".
Lopetegui took charge of the 2010 world champions for the first time in the recent international fixtures - seeing his side overcome Roberto Martinez's Belgium 2-0 in a friendly before thumping minnows Liechtenstein 8-0 in their first qualifier for the 2018 World Cup.
And although the former Porto coach was delighted with the flying start to his tenure since taking over from Vicente del Bosque following a disappointing defence of their European crown at Euro 2016, he is confident his side have yet to get into top gear.
"There's a world of difference from game to game, and the demands on you are different too," Lopetegui told FIFA's official website.
"We expect the team to be capable of meeting every challenge, and that the players are able to come up with their own answers when difficulties arrive.
"I'm certain that in that area the team will respond positively, rise to the challenge and can add a lot more strings to their bow.
"We want a Spain side that is able to draw the best it has out of the players at its disposal. One that's able to take the initiative in games.
"We're pleased about the wins but we're happy about the response we've seen from the players, the behaviour and commitment they've shown, and their determination to take on board all the ideas that we've tried to get across to them over these two games."
Spain take on Italy in Lopetegui's second competitive match, and will also meet Albania, Macedonia and Israel in qualifying Group G.