A tensioning or deflection pulley for a belt drive includes a carrier and a track roller comprised of an inner ring, an outer ring, and a connecting assembly, including a wheel disk extending between the inner and outer rings, and a rib assembly disposed in both sides of the disk in circumferential spaced-apart relationship, for interconnecting the inner and outer rings. The track roller is supported on the carrier by a sealed rolling-contact bearing via a fastening screw. A first sealing element is connected to the track roller on a carrier-distal side, and a second cap-shaped sealing element is disposed between the carrier and the track roller and detachably secured to the inner ring of the track roller to thereby seal the track roller on both sides.