Mata, who would walk into most teams at Euro 2012, is battling with talented and experienced players like Andres Iniesta, David Silva and Cesc Fabregas for a place against Italy in Sunday's Group C opener in Gdansk, Poland.
Amid 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 contribute his best if he does make an appearance.
"It's true that I played a lot of minutes at Chelsea this season and felt like an important player," Mata told a news conference on Thursday at Spain's training base in Gniewino.
"I just need to keep working now to try and get into the starting XI for the national team," he added.
"But 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 as we all have the same goal which is to win the competition."
IMPACT PLAYER
Even if Mata is not among Del Bosque's first choices, he is the kind of impact player any coach would be thrilled to have on the bench.
Another is Pedro, whose season at Barcelona was disrupted by injury but who began towards the end of the campaign to show the form that won him a place in the 2010 World Cup final team.
"Logically, at some moments I saw myself not making the team [for Euro 2012]," Pedro told Thursday's news conference.
"But luckily I was able to end the season with confidence and in the King's Cup final I felt very good," added the 24-year-old, who scored twice in Barca's 3-0 Cup victory against Athletic Bilbao.
"The coach will decide if I can contribute to the team and I will be working 100 percent towards the moment he decides I am able to play."
Both players took the chance to offer their condolences to the family and friends of former Sporting Gijon coach Manuel Preciado, who died of a heart attack on Thursday aged 54.
