Former Chief Cabinet Secretary Seiroku Kajiyama on Monday denied that he will be tapped to replace Prime Minister Ryutaro, who, according to rumors, may be forced to step down in a few months due to his economic policy failures."Some people say that I still have ambition (to become prime minister), but this is not true," Kajiyama said in a speech at the Japan National Press Club. "I would like to remain a player in the back line, giving advice to the administration," the 71-year-old veteran politician said, likening his role to a defensive position in soccer.Kajiyama, who proposed a government plan to infuse huge sums of public money to stabilize the nation's teetering financial system, has been rumored as a potential candidate to take Hashimoto's post. The Hashimoto administration is doing well amid current economic difficulties, Kajiyama said."Nobody other than (Hashimoto) could serve in the position now," he added. Hashimoto has been under severe criticism for his failure to implement fiscal restraint policies and for increasing the public burden amid a troubled economy. Kajiyama defended Hashimoto, saying no one could have predicted the financial system would be so badly shaken, exacerbating the poor state of the economy.