We all take /use references at every point of our recruitment cycle, not mandatory some times reference works most times reference may not be suitable on the requirements we handle.. But we always keep it aside , one option is try to connect them on LinkedIn and keep them share your opportunities to them or message them on LinkedIn when possible .. i always use it for niche skills hiring /Leadership hiring.... Please dont expect immediate results but once you get profile you dont need to worry that he/she will join and not to worry about caliber of the profile as he /she will recommend the person he is trust worthy and on the disclaimer sense some people wont join due to valid or genuine reasons that you could always write too.. When doing Background checks, that is huge pool of data we miss , is better to take details of their reporting managers and maintain separate pool , it is not wrong but wise way of working through challenging positions it sure to help ....
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