The 20-year-old, who has represented England at Under-18 and Uunder-19 level, insists he has no intention of clocking up bench time again after failing to break into the Huddersfield first team last season.
Eastwood will compete directly with fellow youngster Jon McLaughlin for a place between the sticks during his stay, which runs until the end of the year.
He told the Telegraph & Argus: "Nothing's really been said so far. We're both fighting for that number one spot as nothing is nailed down.
"But until it is, I'm fighting to make sure I'm number one. I've been number two at Huddersfield and I've come here to play first-team football. All I want is a chance and hopefully that's all I'll need."