The Chelsea FC star was left out of the national team squad for their forthcoming friendly games as they prepare for the World Cup in Russia this summer.
Morata has made a mixed start to life at Chelsea FC since signing for the west London club from Real Madrid last summer.
He has netted 10 goals in the Premier League so far but his strike in the FA Cup win over Leicester City last weekend was his first goal since Boxing Day.
The 25-year-old has struggled for form and fitness in recent months but he will be hoping to hold down a regular spot in the first team at Stamford Bridge between now and the end of the season.
And former Chelsea FC striker Costa has lifted the lid on his reaction to Morata being omitted from the Spain squad this summer.
Costa is quoted as saying by Metro: “I do not feel more liberated, I miss him, we get along very well.
“Morata is a great person, a great footballer, he is having a bad time but he is starting to score again.
“I want him, me and everyone if possible. The pressure is the same, being a forward of the National Team represents a lot.”
Chelsea FC will return to Premier League action after the international break with a crunch clash against top-four rivals Tottenham Hotspur at Stamford Bridge.
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