The 36-year-old has scored a stunning five goals in his last two visits to Norwich, including all four in a 4-0 victory in July 2020.

Antonio joined Watford on a free transfer last month, but has yet to kick a ball in anger.

Since being an unused sub in a 2-1 loss against Stoke the day after his arrival, Antonio has not featured in a matchday squad.

Hornets head coach Alessio Dionisi said the player has been suffering from an issue – believed to be a quad injury – and could not offer a potential timeline for his return.

“Michail has a hamstring and abductor problem,” he said.

“Now he works to arrive in good shape.”

The Watford boss is not expecting any of his injured players to return before the upcoming international break.

"Against Norwich, there won't be [Kwadwo] Baah, [Jeremy] Ngakia, [Edoardo] Bove, [Soumaila] Coulibaly and Antonio," he said.

"Now it's difficult to know [who will be back first].

“They will probably be ready after the international break... probably.”

Watford are a place and a point behind Norwich in the Championship table.

“We are an important club in this league, but I know our situation,” said Dionisi.

“I wanted more points.

We have 11 points at the moment.

It is this and it is normal to work better and arrive at a best result.

“I didn’t like the first half against Wolves - a big team.

I spoke about Wolves, but I want to see other things.

“The match was difficult and in the second half my team played better with and without the ball.

“But now it is important to improve and show our quality.

It is not easy because every match is difficult.”

Meanwhile, midfielder Hector Kyprianou has rubbished claims players were kept in a 'prison-like boot camp'.

Watford players spent two nights this week at the five-star Sopwell House hotel, close to the club's London Colney training ground.

One national newspaper claimed the players were 'seething' at the decision, but Kyprianou insisted he had a great time.

"We went to Sopwell House on Tuesday night and Wednesday night," he told BBC Sport Three Counties.

"I haven't read much about it, but I've been told that people have said it was 'like a prison', but I can assure you it wasn't like that.

“It was possibly the complete opposite.

We went to a nice hotel, after training we were allowed to go home to see our families and stuff, and then we reported for dinner, where we were together with the team, having good news and bonding.”