If they fought as amateurs then Joshua won cos his wiki page tells ya the 3 amateurs he lost to - Nistor - 2011 European championship Medzhidov - 2011 world championship Whyte - 2009
Just found it on http://www.boxing-scoop.com/show_boxer.php?boxer_ID=13812 10th February 2012 and Joshua won 9-7 on points