Mata, who would walk into most teams at Euro 2012, is battling with players like Andres Iniesta, David Silva and Cesc Fabregas for a place against Italy in Sunday's Group C opener in Gdansk, Poland.
With such stiff competition, he is realistic about his chances of being called on to help Spain become the first nation to win back-to-back Euro titles with a World Cup in between.
But the 24-year-old said he was focused on getting himself in peak form so he can be at his best should he make an appearance.
"I played a lot of minutes at Chelsea this season and felt like an important player," said Mata at Spain's training base in Gniewino.
"I just need to keep working now to try and get into the starting 11 for the national team."
"However, there are a lot of players who have been here a long time who have also earned that right.
"Whether I am playing or not playing I will always be supporting the team.
"We all have the same goal which is to win the competition."
