Mauricio Pochettino believes it is unfair to compare the impact of Enzo Fernandez at Chelsea to that of Arsenal’s Declan Rice, as the teams prepare to face each other at the Emirates Stadium on Tuesday.

England international Rice joined Mikel Arteta’s side from West Ham last summer for £100million, less than the £107m it cost to take World Cup winner Fernandez from Benfica to Stamford Bridge in January 2023.

The fee for the Argentinian was a British record at the time, though the club have since surpassed it in signing fellow midfielder Moises Caicedo from Brighton for £115m.

Rice has won plaudits for his transformational effect on Arsenal’s midfield, helping to forge a sturdier, more cohesive side than the one that fell away in the final weeks of last season’s Premier League title race.

By contrast, Chelsea’s league position has not markedly improved in the 15 months since Fernandez arrived in west London, and despite clear flashes of his obvious talent and range of passing, question marks have remained over whether the club got value for money.

However, his countryman Pochettino called for perspective on the obstacles that his player has had to contend with since arriving in England.

“Declan Rice was playing for West Ham, an English guy who knows the Premier League, knows the language,” said the 52-year-old.

“For Enzo, after the World Cup to arrive here, in a team that was inconsistent, difficult to get positive results, always it was really difficult.

“In summer he was involved in too many games and he arrived late in pre-season, hasn’t had a holiday in the last two years.

“Too many negative things happened. (It was) difficult for him to adapt, his family. It’s not easy to adapt and perform so quick.”

Fernandez was responsible for creating Chelsea’s best chance of Saturday’s FA Cup semi-final defeat to Manchester City, hitting an incisive, raking pass from deep that sent Nicolas Jackson through on goal, but the striker could not finish.

He has scored three Premier League goals and made four assists since moving from Portugal in the immediate aftermath of Argentina’s 2022 World Cup triumph, but Pochettino insisted the best is yet to come from the 23-year-old.

“For sure he is going to be much better next season, after the experience of the whole season in this squad and this team,” he said.

“He’s more experienced, he gets better feelings. The whole season is good for him to learn. Even if he is a world champion, he needs to adapt to the Premier League and to this club. For me, there is no doubt that he is going to be much better.”

Pochettino said there have been no discussions over the future of striker Romelu Lukaku, currently on a season-long loan at Roma, but appeared to hint that the door could be open for a return.

The 30-year-old has scored 18 goals for the Serie A side this campaign after telling Chelsea last summer that he wanted to leave.

“He’s a Chelsea player, so for sure we will pay attention,” said Pochettino. “It’s an option. But still we did not take any decision.”