Alvaro Morata admitted that it was a mistake to play through the lingering back pain that had contributed to his slump in form and confidence for Chelsea.

Morata scored eight goals in his first eight Chelsea appearances following a club-record £58 million move from Real Madrid last summer, but since then, he has struggled physically and mentally with the demands of a relentless schedule.

“Chelsea is a big club, a club that has given me the opportunity to play as a starter, to grow even more,” Morata told Movistar. “It’s a team where I’m very happy, where I started well until I had some physical problems.

“I made a mistake in that respect as I played with pain [earlier this season]. I went through a poor spell where I missed important goals but I wasn’t well physically and mentally. I have to grit my teeth and do all that I can to return. We have the Champions League tie [against Barcelona].”

The Spain international returned to the pitch as a substitute in Monday’s 3-0 win over West Bromwich Albion at Stamford Bridge, producing a lively 30-minute cameo after replacing January signing Olivier Giroud up front and forcing several impressive saves from Ben Foster.

It was an encouraging sight for Antonio Conte, who has been without Morata for almost a month since the striker was sent off during extra time of Chelsea’s penalty shootout win over Norwich City in a dramatic FA Cup third-round replay.

On Friday, three days before the victory against West Brom, Conte acknowledged that he was “a bit worried” about Morata’s health, but Morata later responded to a fan on social media by declaring himself fit.

Conte said after the West Brom win that he wants both Giroud and Morata to gain sharpness on the pitch ahead of next week’s Champions League round-of-16 first-leg clash with Barcelona, when Chelsea will be heavy underdogs despite playing at Stamford Bridge.

Barcelona have been in imperious form this season, led by Lionel Messi. The Argentine superstar has registered 20 goals and 10 assists in 23 La Liga appearances and will be looking to end a bizarre eight-game scoring drought against Chelsea when the two teams meet on Tuesday.

“There’s no way to stop Messi,” Morata said. “The only way is for him not to have a good day, but that’s difficult because most of the times he has good days. Let’s hope we can get a good result there [in the second leg], play well defensively and find spaces.

“But first, we have to play a good game here and get a good result, which is not easy against Barcelona.”