But Lampard has contradicted that assessment and says Rudiger is scheduled to undergo further assessment early next week.

“No, he’s not fit. I saw the quotes, whether there was a miscommunication somewhere, he’s not fit,” said Lampard.

“He’s going to see a consultant on Monday because he has an ongoing issue in his pelvic area which is bothering him so I was a bit surprised by the quotes.

“It’s a miscommunication, he’s not there.”

Lampard, who saw his side’s seven-match winning run ended by Manchester United in the Carabao Cup in midweek, also remains without N’Golo Kante.

France midfielder Kante has not featured since before the last international break because of a groin issue but is closing in on a return.

Lampard is keen to have the influential pair back in contention as soon as possible.

“Every player in the squad that’s not available is disappointing but it comes with the territory, injuries are there,” said Lampard.

“Himself (Rudiger) and N’Golo are obviously top players and carried over injuries from last season – different injuries now but it’s been a domino effect.

“The players will be more frustrated than anyone else because there’s nothing worse than being a player when you can’t have input into what the team is doing every week, disappointing for me because I want to be able to select from them.

“We’ll keep going and as soon as both of them are fit – N’Golo’s close, he’s working with the team now – we’ll be all the better for that.”

Chelsea sit fourth in the table from following successive top-flight wins.

A trip to face the winless Hornets at Vicarage Road represents an ideal opportunity to extend that impressive streak.

However, Lampard is wary of his players becoming complacent against struggling opposition.

“Ever since we’ve been on the winning run – which obviously ended in midweek – the game became more dangerous because of the idea of any over-confidence, which I work against,” said Lampard.

“We saw what they did last year, getting big results and regularly being a very strong team and making the FA Cup final.

“We cannot underestimate the team that will be hurting because they haven’t won for a while and will have every ambition to try and win this game, so I certainly have even more focus on what we need to do.”

Midfielder Ross Barkley remains sidelined by an ankle injury but centre-back Andreas Christensen is closing in on a return following a hamstring problem.