Stuart Reed, the former Chief Supply Chain Officer at Motorola who led a transformation of the company’s supply chain that ultimately earned him the presidency of Motorola’s key business unit, resigned this week, not long after new CEO Greg Brown took direct control of the division.

Reed had come to Motorola from OBM, and was among the first in the industry with the title of Chief Supply Chain Officer. After his successful efforts in Motorola’s supply chain transformation, he was promoted just last July to head the company’s mobile systems business, which includes cell phones such as the Razr, but which had been struggling before Reed took the top spot. Many viewed it as a good sign for the profession that a supply chain executive was given general business executive duties, especially for a spot as important as Motorola’s wireless business.

Alas for Reed, former CEO Ed Zander was replaced by Brown last fall. Five weeks ago, he took direct control of the mobile division, which is seen as the key factor behind Motorola’s overall financial and stock market swoon, as the RAZR line has grown old and hot new cell phones haven’t been released. The division accounts for about $19 billion of Motorola’s $36 billion in shares, but it has fallen into third place in global market share.