The West London outfit have yet to snatch a win in the Premier League this season and Granero is hopeful that that will change this weekend against Southampton.
"We know this is going to be massive for us," Granero told the club's official website. "We play at home against one of our rivals.
"We know the supporters are with us and they deserve more than we are giving to them. All we can do is continue training hard and give everything on the pitch on Saturday."
QPR have taken four points in 11 games and sit at the bottom of the league table.