India's Olympic hero Vijender Singh, who finds himself at the centre of a drug scandal, has made himself available for an out-of-competition dope test by NADA officials.After refusing to undergo tests ever since the scandal broke out about a month back, the boxer's urine and blood samples were taken this morning.But it is learnt that the tests will not be specifically for heroin. The news that Vijender took the dope tests today was disclosed by Sports Minister Jitendra Singh, who also advised the boxer to go for a rehabilitation if found guilty. The NADA, which is an autonomous body, was willing to conduct a regular out-of-competition dope test on Vijender.But the Agency had expressed its inability to test the Olympic bronze-medallist for heroin citing World Anti-Doping Agency's protocol.