The Hornets lost 3-2 at Arsenal on Sunday as their five-year stay in the top-flight came to an end.
Deeney pulled one back from the penalty spot and former Arsenal man Danny Welbeck struck to give them hope – but it was not to be and Watford will be plying their trade in the Sky Bet Championship next season.
"First of all from the mental side it will be equal. How much they (Chelsea) want it compared to how much we want it.
"I don't think that was the case today because of the necessity Watford had, the way they had to approach the game was different to us and you can see that. Hopefully Saturday will be very different."
Arteta confirmed after the game that Shkodran Mustafi's hamstring injury will not only see him miss the FA Cup final but also the start of next season.
Mustafi joins fellow defenders Calum Chambers and Pablo Mari in the treatment room, with Arteta admitting the club need to "address" that in the transfer market.
One option already available to Arteta is Sokratis Papastathopoulos, who has played just one minute of football since the season resumed.
The 32-year-old was a regular under former boss Unai Emery but has slipped down the pecking order since Arteta arrived in December.
Despite his lack of football, the PA news agency understands Sokratis will not ask to leave the club this summer and is willing to stay and fight for his place in the team, with his contract having another year to run.