Maurizio Sarri fears N’Golo Kante’s hamstring injury will keep him out of Chelsea’s coming fixtures with Eintracht Frankfurt and Leicester City.

The influential midfielder was replaced by Ruben Loftus-Cheek early in the first half of Sunday’s 3-0 victory over Watford, and he could be absent as they pursue progress to the Europa League final and third place in the Premier League.

Defeating Watford, coupled with Arsenal being held by Brighton later on Sunday, has already ensured that they will finish in the top four, but the much-maligned Sarri is targeting the type of successful conclusion to their season that had long appeared beyond their reach.

A wider concern surrounding the 28-year-old Kante’s potential absence is that despite victory, Chelsea long appeared tired and lacked intensity before taking the lead early in the second half, and discussing Kante’s condition, Sarri said: ‘The problem is with his hamstring.

‘But I made a mistake because, probably, he had to rest. Sometimes it’s very difficult to put on the bench a player so important like [Eden] Hazard, like Kante, but you have to do it.

‘We have to wait until the morning [to determine the severity of the injury], but it’s very difficult to recover him for the next two matches. We have to try and recover him for the [potential Europa League] final.’

Watford manager Javi Gracia recognised that his team may have been distracted by the prospect of their FA Cup final against Manchester City later this month, and he explained: ‘We have to play the final. It’s normal for it to be on our minds, but we were focused on this game [against Chelsea].

‘We have to finish the league next week, and then have an important final. If your behaviour always is defending badly at corners and free kicks, I’d be worried. But it’s not like that. I’d prefer to be optimistic.’