The Sun says he has failed to impress Avram Grant, who took over from Jose Mourinho within a month of Belletti's arrival, and is likely to be sold this summer.
Chelsea could use the right-back, 31, as part of their bid for Valencia's superstar striker David Villa.
Belletti, who still has another year of his £35,000-a-week Chelsea contract to run, is in no rush to quit Stamford Bridge.