Glen Harris has promised to go full tilt at this weekend’s SSE FA Women’s Cup fifth round tie at home to Chelsea.
Belles also welcome the reigning champions and FA Cup holders to the Keepmoat Stadium next Thursday in their FAWSL1 opener.
But Harris says it will not be a case of leaving anything up his sleeve for the league game.
“You only get one crack at the cup so we’ll be giving it everything on Sunday,” he said.
“We want to go further in the competition and, like a few of the girls have already said, if you want to be the best then you’ve got to beat the best.
“In a way it’s a little bit disappointing to have back-to-back games with them because it’s taken a bit of an edge off the opening league game.
“But we won’t be any less prepared or focused for either of the games.
“It might be a good time to play Chelsea because they’ve had a few girls away on international duty recently.
“We’ve been together throughout pre-season and the girls have put some really good work in.
“We’ve got a couple of niggles but, in the main, we’re looking good and are really looking forward to it.
“The girls are going into the new season fit and strong. We’re ready for it, and we can’t wait to get started.”
Midfielder Carla Humphrey, on loan for the season from Arsenal, and defender Rhiannon Roberts are slight fitness doubts for Doncaster.
Chelsea could include former Belles stars Millie Bright and Bethany England in their squad.
Tickets are priced £6 for adults and £1 concessions.