A wear-resistant annular seal assembly has a plurality of interlocking one-piece seal segments interleaved with a plurality of two-piece seal segments. The seal segments are made using wear-resistant rigid material such as steel, stainless steel or a composite material. In one embodiment the seal segments are coated with a fluoropolymer. A straddle packer includes a first and second spaced apart ones of the wear-resistant seal assemblies and a linear force generator for urging the first and second seal assemblies to a seal-set condition.