A magnetic read transducer including a magnetoresistive sensor is described, as well as a fabrication method thereof. The magnetoresistive sensor includes a cap layer overlaying a free layer. The cap layer is situated with a first thickness to absorb boron from the free layer. The magnetoresistive sensor is annealed, and boron is diffused from the free layer and absorbed by the cap layer, improving the magnetic performance of the free layer. The cap layer thickness is then reduced to a second thickness, thereby reducing the shield-to-shield (SS) stack spacing of the magnetoresistive sensor and allowing for increased areal recording density.