Carnegie head to Castle Park for an eagerly-anticipated Yorkshire derby which is crucial for both sides in their bid for top-four momentum.
In-form Doncaster are up to second in the Championship and have not lost in the league since falling 27-20 at Headingley in October while Redpath’s team are fourth but just two points behind their rivals.
“They are good, with a physical pack, a very good drive and good options of it, too,” said Redpath.
“They are strong in the midfield area when they have a chance can have real crack at you.
“Big games are won and lost by small margins and we will have to be sharp on them on Saturday.”
Historically, Carnegie have a poor record at Doncaster but they are not concerned by that ahead of today’s showdown.
They recovered from a loss at London Scottish by winning against Cornish Pirates last weekend and arrive in positive mood.
“Getting that win was huge for us and also the manner of how we played,” added Redpath.
“We finished off two or three opportunities out wide that we’d not executed before.
“People got a little bit edgy that we’d lost one out of eight games in eight weeks but that was a tight game at Scottish and one we should have won. We got our heads down, knuckled down to the game v Cornish and won it so we can look forward to a new challenge now; Donny have been pretty good this year so we need to be at best to get close to them.”
He has made just one unforced change to his side as he rotates his tighthead props with Rob O’Donnell starting and Ben Hooper dropping to the bench.
Richard Beck, meanwhile, suffered a head injury against Cornish and Mike Myerscough has been ruled out with appendicitis so captain Chris Jones moves to the back-row to replace Beck allowing Dean Schofield and Matt Smith to form the second-row.
Jarad Williams is added to the bench to replace Myerscough but there is no place for fit-again Kevin Sinfield.
Doncaster suffered a major blow when No 8 Ollie Stedman –who had scored five tries in their last two games – pulled up with a hamstring strain in training. Irish fly-half Declan Cusack returns from a concussion, though, to replace Simon Humberstone who reverts to the replacements bench, while captain Michael Hills and on loan Leicester forward Tiziano Pasquali are also available.