little off the ground via a jack and hold the tire at 9 and 3 o'clock. Try to wiggle it - it should not move. Do the same hold at 12 and 6 o'clock position. If not sure repeat this test on the other side or front of car - as a comparison.
I'd also check the caliper assembly - does it wiggle a bit? Maybe a caliper hold down bolt needs to be tightened?
I'm assuming this isn't an issue with just the pad rubbing - that could be a caliper piston not re-tracking due to being seized/frozen.