Halfbacks rhymes with:
buybacks, comebacks, cutbacks, drawbacks, flashbacks, fullbacks, givebacks, greenback's, greenbacks, kickbacks, leasebacks, leatherbacks, paperbacks, paybacks, pricklebacks, pullbacks, quarterbacks, razorback's, razorbacks, rollbacks, setbacks
Halfbacks sounds like:
halbach, halbig, half's, halfback, halifax, halves, helbig, hellbusch, helps, hlavac, hlavacek, hollabaugh, hollibaugh, hollobaugh, holvis, holvis', holvis's