Gracia stepped in for the sacked Marco Silva this week.
"I think the most important thing is the confidence of the players," Gracia explained to Watford's official website. "They have played very well at times this season and they can do it again.
"Confidence, work hard and the results will arrive.
"I know many players because I've seen all the matches of Watford this season. I know all the players and there are many injured players.
"We'll try to recover them and altogether try to make a good team."
Holebas only signed a new deal at Vicarage Road a fortnight ago, but this may have been with a re-sale value in mind.
It is stated Galatasaray will pay €600,000 for a half-season loan, with the option to purchase the 33-year-old defender if they take a shine to him.