The main objective of primary cementing is to provide complete and permanent annular isolation from mechanical and chemical stresses during drilling and production. Through-tubing rotary drilling (TTRD) technology presents its own challenges to cementing design. Use of bicenter drill bits that achieve a larger openhole size than the pass-through diameter introduces centralization difficulties and adds complexity to drilling-mud removal before cementing. By challenging common design practices, a design was proposed that combined low- and high-rheology fluid properties to achieve the objectives for cementing a 2 7/8-in. liner.