The 27 year old Spang played 77 games for the Texas Stars last season, scoring 10g, 27a for 37 points. This made Spang the highest scoring defensemen on the Texas squad for 2010-2011 while also setting a personal best point total at the professional level.
This move gives Dallas some interesting flexibility on the D-corp next season. With Larsen expected to make the push out of camp for a roster spot, Spang looks appealing as a call-up option. With decent size (6', 205 lbs) and an offensive spark Spang will figure very prominently in the Texas Stars system again next season. He's definitely one to keep an eye on, and I would expect Dallas to give him a good look in camp.
Heika has some interesting tidbits about the defense situation for Dallas next season, so please go give his article a look before it gets behind the paywall.