Frank Lampard will be praying that the Croatian’s Achilles problem isn’t too severe as the 25-year-old continues to be his very best player this season.

N’Golo Kante was the first name on the team sheet for Chelsea’s latest name winners but today the Blues have a brand new undroppable participant: Mateo Kovacic.

Recently, the Croatian has become the player that many expected him to become from the moment Inter signed the midfielder from Dinamo Zagreb in 2013.

After a challenging first season on loan from Real Madrid, Kovacic is now Frank Lampard’s only untouchable at Chelsea, which only makes the Achilles injury sustained by the 25-year-old in Tuesday’s FA Cup triumph over Liverpool all the more about.

Kovacic was forced off only three minutes before the break following a crash with Sadio Mane and the Blues battled their way to a deserved 2-0 victory, losing the midfielder for an elongated time period would be a calamity for Lampard.

The timing certainly could not be worse, for both the player and his team.

Kovacic fought under Maurizio Sarri last term and Chelsea’s decision to make his loan deal permanent arguably had more to do with the club’s move ban compared to his performances on the field.

The coming of Lampard, then, was crucial to Kovacic’s development.

“I have great communication with him,” that the Croatia international said. “I’m working on my poor sides of the game.

“I’m talking to him a lot and I am analysing my match. I believe I’m becoming a better player but it’s normal because I’m getting more mature. I am a fantastic age, so I feel great.”

Lampard has been impressed with Kovacic’s improvement. Really, it was telling that he was the only player singled out for praise by his supervisor following the chastening 3-0 Champions League reduction to Bayern Munich.

“Kovacic played a personality and quality that make you go,’Okay, he can play pretty much any team with that degree’,” the Blues boss eager.

Hardly surprising, then, that Kovacic is firmly in pole position to win Chelsea’s Player of the Season awards.

Lampard will, therefore, be mightily worried by the possible loss of one of the most reliable actors, not least because Chelsea are already short on options in midfield.

Kante will remain sidelined by injury for a further fortnight, while Jorginho is suspended for the next few matches.

The fit-again Ruben Loftus-Cheek racked up 90 minutes for Chelsea’s Under-23s in Monday’s 1-0 win over Everton, whom the Blues face next in the league before matches against Aston Villa and Bayern Munich.

Chelsea also have injury problems out broad, with Willian having also limped off from Liverpool. It is not yet known when Christian Pulisic will recover from the muscle problem that has kept him out since New Year’s Day and while Callum Hudson-Odoi could return this weekend, the England international has not trained for a month.

Elsewhere, first-choice striker Tammy Abraham has missed a month of football with an ankle issue, even though a minor knock kept centre-half Andreas Christensen from the Liverpool game.

Chelsea’s injury crisis has arrived at a most inopportune moment, with Lampard’s side struggling to hold on to fourth place in the Premier League.

Manchester United and Wolves are now just three points further back, while a win for Carlo Ancelotti’s Everton on Sunday would put them in contention for a Champions League place despite now sitting in 11th in the standings.

The Blues, of course, only have themselves to blame in this respect. After a bright start to the season, they’ve failed to stand up back-to-back wins since November and have been particularly poor in the home.

However, Lampard has been buoyed by the remarkable cup triumph over runaway league leaders Liverpool.

Ross Barkley put in his best performance of the season up to now, while 18-year-old Billy Gilmour was the star of this show, walking away with the man-of-the-match award due to some midfield masterclass that drew praise from among Scot’s childhood idols, Cesc Fabregas.

“I have been learning off [Kovacic and Jorginho] in training and watching them in matches,” Gilmour said after the game. “To play alongside both of them was brilliant.

“Hopefully, Kova is back and fit for the weekend.”

That now seems unlikely, with Lampard then admitting that Kovacic’s Achilles problem looks”worse” than Willian’s.

He’ll be praying that is not true, though. Of all of the players now struggling with injuries at Chelsea, Kovacic is the one that Lampard wants back in his beginning line-up when possible.