Alvaro Morata considered leaving Chelsea just a year after joining from Real Madrid in the wake of a disappointing first season and heartbreak at missing out on the World Cup.

The striker moved to Stamford Bridge last July for a reported fee of £60million, then a club record for the Blues, and scored six goals in his first six Premier League games in an encouraging start to life in England.

However, a mysterious back problem blighted the rest of his season and he only scored five league goals between late September and May, with his loss of form leading to Julen Lopetegui leaving him out of Spain's squad for the World Cup.

The blow of not going to Russia prompted Morata to think seriously about heading back to Spain or Italy, where he thrived with Juventus, although he says a return to Real Madrid was "never an option".

Recalling how he felt after being left out by Lopetegui, he told a news conference: "'F***, how am I going to live the summer without going to the World Cup?' It was a tough moment.

"I'm going to do everything possible to go to the next one. It was a difficult moment because I expected to go.

"I don't hold a grudge against Lopetegui. It was his opinion and I did not have my best season, either. I wish him the best and more so now that he's at Real Madrid.

"Yes, of course I considered going back to Spain or Italy. But you can't always escape reality. I left here [Spain] in order to be at the World Cup, and I didn't go.

"Of course, it was my worst moment. When you start to play football and watch World Cups on TV, it's your biggest dream."

Morata believes Maurizio Sarri's arrival at Chelsea and becoming a father helped him come through the "disaster" of his first year in England.

"Last year started well but in the end it was a disaster. I didn't even know where I was when I went out to play," he admitted.

"I've become a father, I have a new coach, I've returned to the national team. A lot of important things have changed my life, especially my two sons, who are a special motivation and now I hope everything goes well on the pitch."

Spain's Morata was recalled by Luis Enrique for the UEFA Nations League matches with England and Croatia this month, having started the season in good shape to help Chelsea to four wins from four league games.

The 25-year-old felt anxious returning to the national team but has been encouraged by talks with the new head coach.

"I feel like it's the first time again. I was almost nervous yesterday. I arrived an hour and a half early!" he said.

"Luis Enrique told us he wants Spain to get back to winning and that everyone should know who Spain are.

"He asks for a lot of intensity, a lot of concentration. From having spoken to him, he seems a very sincere person, who is eager to win."