The Hornets make the short trip to the Emirates Stadium for their FA Cup sixth-round tie - with a place at a Wembley semi-final the prize for the victor.
Arsenal, in search of their third FA Cup success in as many years, came through a replay at Hull in midweek to set up a clash with Barclays Premier League rivals Watford.
Wenger lost both of his centre-backs on Tuesday as Gabriel and Per Mertesacker were forced off with injuries.
But he is hopeful both will be available for Sunday, while fellow defender Laurent Koscielny could also be fit for a recall having recovered from a calf injury.
Even though Wenger could have the trio at his disposal, with a Champions League tie in Barcelona and a tough Premier League trip to Everton to come inside a week, he may have to look carefully at who is given the nod against Quique Sanchez Flores' side.
And the Frenchman is wary of the threat that Watford's two strikers can possess - with the visitors looking to spring a surprise by knocking out the record 12-time winners of the trophy on Sunday.
"They have done extremely well," Wenger said of Watford's first season back in the top-flight.
"It looks like the Championship teams that come up now deal very well with the Premier League regime.
"You have Watford who are doing extremely well
They are very prepared and very efficient
They have two strikers who are very efficient with Ighalo and Deeney and we worked very hard to control the game (last time we played them).
"They give us a tough time
When we played against Watford in the Premier League, Deeney had not scored I think for a long time
After us he started to score but during the game I was impressed by him
He's a good player.
"They have a very good understanding between the strikers and the quality between our two centre backs will be vital on Sunday."
Wenger rubbished links of an Arsenal move for Deeney in the January transfer window before seeing his own strikers all hit a collective barren spell in front of goal.
But, with Alexis Sanchez scoring the equaliser in last Saturday's draw at rivals Tottenham and both Olivier Giroud and Theo Walcott hitting two apiece in the win at Hull, Wenger believes his side can now put together a strong run of form - having not ruled out success across all three competitions this season.
"I haven't given up on the Premier League at all and I've said that many times, nor the Champions League," he added.
"We have to take care of the next minute and the next minute is an FA Cup game
Is it the best chance to win a trophy? It's still far away
We must win the next game and prove that we can show consistency again.
"I feel we can have a run but we know how quickly it can change - we lost two games and suddenly looked like we would be in the Championship next year so it is game by game and all we know is we can not afford any more slips ups like we did against Swansea (a 2-1 home defeat)."
Source : PA
Source: PA