County included Alex old boys Robbie Savage, Rob Hulse, John Brayford and James Bailey in their side, but their former club did not roll out the welcome mat.
Clayton Donaldson missed two good chances for Crewe before Shaun Miller drilled into the side-netting after latching onto Calvin Zola's flick.
Derby were unlucky not to get a penalty when Danny Blanchett looked to have hauled down Ben Pringle in the box and only a superb reflex save from Rhys Taylor kept Barker's goalbound header out.
Alex saw more chances go begging as Dave Artell headed wide from Ashley Westwood's cross and Donaldson's touch proved too heavy after being picked out by Lee Bell.
But Crewe deservedly took the lead on the stroke of half-time when Donaldson turned Miller's cross into the box and Barker sliced into his own net under pressure from Zola.
Miller thought he had doubled the advantage but his side-footed finish came back off the upright with goalkeeper Stephen Bywater beaten.
County piled on the pressure but were restricted to long-range efforts with Taylor dealing well with testing shots from Bailey and Kris Commons.