NEW: Ernst Tanner has built a powerhouse at the Philadelphia Union.
But my @us.theguardian.com investigation has shown wide-ranging allegations of misbehavior throughout his 7-year tenure.
Tanner denies the allegations, and was investigated by MLS this year.
MLS executive who built a powerhouse faced allegations of sexist, racist and homophobic behavior
Philadelphia Union sporting director Ernst Tanner denies the allegations, which prompted a recently-concluded MLS investigation that could not corroborate them