Orr featured regularly at right-back at the start of the season before falling behind Wales Under-21 international Adam Henley in the pecking order shortly after Henning Berg was appointed as Steve Kean's successor in the Ewood Park hotseat.
On-loan Chelsea youngster Todd Kane is expected to make his third consecutive Rovers start on the right-hand side of defence against Brighton on Tuesday night as Henley continues his recovery from a hamstring injury, but new boss Appleton insists Orr features in his first-team plans
"He'll be vital for us between now and the end of the season," he told BBC Radio Lancashire
"He's got vast experience of the Championship, he's very vocal, he's a good character and he's someone that I would rather have in my side than up against me."
The 30-year-old former QPR defender has made 12 starts for Ipswich and is set to play his final game for the club at Bristol City on Saturday.
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