The D on the away jerseys of the Detroit Tigers is a regular English D.
It is a Nike font (Ithaca).
The font that is used on this jersey is Futura Condensed. It was picked out by the marketing department for this group to make the name more recognizable.
The font is Futura Condensed. In 1997, the team switched to rounded numbers on the jersey to match the font on the helmets. Click on the link below for more information.