Motorola Chief Technology Officer Padmasree Warrior has followed CEO Ed Zander out the door. The company said on Monday that she had left and Chief Strategy Officer Rich Nottenberg would temporarily assume Warrior’s role as head of Moto’s thousands of engineers and caretaker of the vendor’s overall technology vision.

Warrior had worked at Motorola since 1984 and had served as CTO since 2003, achieving the highest executive post held by a woman at the Chicago-based company. Her departure comes just one business day after CEO Ed Zander revealed he would step down on Jan. 1, when Chief Operating Officer Greg Brown would assume the top job.

The departure of Warrior is the latest in a series of executive changes as Motorola’s poor financial performance and falling handset market share have shaken up the company’s top ranks. Executive vice president Ron Garriques left in April after failing to come up with a follow-up for the enormously popular Razr. The Razr triggered Motorola’s rapid ascent to handset prominence around the world, but after the Razr lost its luster, Motorola saw its market share dip back to pre-Razr levels. Chief Financial Officer David Devonshire departed soon afterwards.

During her four-year tenure, Warrior was part of the executive team that rode the Razr’s success to the top, but she also had several other major impacts on the vendor’s strategy. She oversaw Motorola’s seamless mobility initiative, designed to link Motorola’s wide-area and home networking divisions through complimentary wireless technologies. She also transformed Motorola’s networks group into a WiMAX company, leading to its big deals with Sprint and Clearwire for the 4G technology. Reuters and other media sources reported Motorola declined to comment on whether Warrior left the company voluntarily or was forced out.

The growing shake-up in Motorola’s ranks may not be enough for some of Motorola’s activist investors. Billionaire Carl Icahn, who has been a thorn in the side of Motorola management since he accrued a 3% stake in the company, said this week that the departure of Zander was not enough to satisfy him. He called for Motorola to be split into its separate divisions, unlocking value for Motorola’s shareholders.