Julen Lopetegui feels coaches should be given more international breaks to develop their teams ahead of the World Cup, but wants his team to take full advantage of their limited time together as Spain prepare for friendlies against Costa Rica and Russia.
The 2010 winners eased to qualification for Russia 2018 by topping a group that included Italy after winning nine of their last 10 matches, but Lopetegui is frustrated by the international calendar.
Spain will not get together again until March, when a prestigious friendly against world champions Germany has been scheduled to be played in Dusseldorf.
FIFA is considering a change in the schedule to have longer, less frequent breaks, but Lopetegui indicated he would prefer a switch that gives him more opportunities to work with his players.
"We're focused on our football right now, we're getting ready for a World Cup," Lopetegui told reporters on Friday. "We only have two international windows to do it, this one and another one in March.
"Both are great opportunities to keep preparing, to set our game style, to be together as a group, to compete and of course to keep improving with the World Cup in view.
"Of course I would like to have more international windows but that's what we all have, us and the rest of national teams. We will try to make good use of the little time we have to stick together and face to difficult teams that might be direct rivals during the World Cup, two strong and difficult opponents that will force us to do our best.
"We have to take advantage of these international windows to clarify concepts of our game and be in the best shape for the World Cup."
Spain will be expected to beat Costa Rica easily, but Lopetegui believes they will give his side a tough test at La Rosaleda on Saturday.
"Costa Rica are a great team, they are in the top of the football scene since four years ago, they were a penalty kick away from playing the semi-finals [of the 2014 World Cup] and they were in first position in their group stage with England, Italy and Uruguay.
"Just with three or four new players they kept the unity as a team that made them reach that stage so tomorrow they will be very demanding, we expect a very demanding match against a team that might be a direct rival during the World Cup and that will force us to be what we actually want to be, a united team, a team that plays well and we will try to win the match.
"We have to keep insisting in what we are doing, we have to believe and be convinced of that and try to consolidate that football situations, with or without the ball. Here the main characters of every game are the players, so we have to set everything so they can shine at their best, we will try to do that as a team and this match is a chance to do that, the same way as the next one in Russia."