The former Arsenal striker had to be replaced after only four minutes of Saturday's 1-1 draw at Tottenham in the Premier League.

Although the Hornets are reluctant to put a timescale on when the former England international will be back, the 28-year-old is likely to be unavailable for "months" starting with this weekend's home match with Bournemouth.

"It's bad news about Danny Welbeck. We need to check a little bit more and that will happen in the next weeks," Sanchez Flores told reporters at a press conference.

"I have no idea how long he will be out, but it's for a long time. It will probably be months rather than weeks."

The news on captain Troy Deeney is more positive, although the forward is still during the recovery process after a minor knee operation in August.

Sanchez Flores added: "With Troy, we are very happy. He's back on the pitch, not with us but alone and working with the medical staff. I hope he is recovering quickly."

A big boost for the Hornets - who remain the only club without a win in the Premier League this season - is Sebastian Prodl, Etienne Capoue and Isaac Success returning to training.

The trio could be in contention for Saturday's match with the 10th-placed Cherries.

Sanchez Flores added: "They came from some injuries but little by little they are training day by day.

"We are just checking at the moment and we need to wait a little bit more."

Australian Associated Press