Grajeda competed for the women's 4 × 400 m relay at the 2008 Summer Olympics in Beijing, along with her teammates Zudikey Rodríguez, Gabriela Medina, and Nallely Vela. Running the start-off leg, Grajeda recorded her individual-split time of 54.71 seconds, and the Mexican team went on to finish the second heat in seventh place, for a total time of 3:30.36.