The Toyota-backed J-League club could lose a sizeable portion of its income after the Japanese government requested Chubu halt operations at its Hamaoka nuclear plant following last March's deadly earthquake and tsunami.
Neither Nagoya nor Chubu, who are staring at a loss of 110 billion yen since the disaster, were available for comment when contacted by Reuters.
However, Chubu's proposed pullout from their sponsorship deal with Grampus comes after the utility serving central Japan, including Nagoya, devised a plan to reduce costs by 130 billion yen by March, following the plant's suspension.
Japan's third-biggest power firm shut its sole nuclear power plant in Hamaoka, 120 miles southwest of Tokyo, last May.
Local media reported that the company, which has sponsored Nagoya Grampus since 2008, has yet to formalise its pullout but confirmed it as an option for cutting its business costs.
Last year's 9.0 magntitude earthquake in north-east Japan and the giant tsunami which followed destroyed a power plant north of Tokyo, triggering a nuclear meltdown.
The disaster left 16,000 confirmed dead with 4,000 still missing while power blackout and fears over radiation wrought havoc to Japanese business, including sport, with major events cancelled and teams going bankrupt as a result.
