(Reuters) - Chipotle Mexican Grill Inc's CMG.N chief marketing and strategy officer has resigned, the company said on Wednesday, just nine days after former Taco Bell head Brian Niccol took the helm at the troubled U.S. burrito chain.

Mark Crumpacker, Chipotle Mexican Grill Inc's chief marketing and strategy officer, is seen in this undated photo from Denver, Colorado, U.S., released on March 14, 2018. Courtesy Chipotle/Handout via REUTERS

Mark Crumpacker will leave Chipotle on March 15, according to a regulatory filing. Crumpacker could not be reached immediately for comment.

Chipotle in a statement thanked Crumpacker for his role in shaping and defining the brand since joining the company in January 2009, and said it would continue its marketing plans while finalizing plans for a new chief marketing officer.

Investors expect Niccol, who demonstrated menu and marketing prowess at Yum Brands Inc's YUM.N Taco Bell and Pizza Hut chains, to tap his professional network for talent.

Chipotle, which used its “Food with Integrity” tagline to build a loyal following, disappointed some investors in September 2016 when it reinstated Crumpacker just months after he was charged with multiple counts of cocaine possession.

He pleaded guilty to cocaine possession in January 2017. Prosecutors agreed to dismiss the case if he received treatment for a year and stayed out of trouble.

Crumpacker’s efforts, particularly food giveaways aimed at wooing back customers after a series of reputation-crushing food safety lapses in late 2015, were costly and failed to resonate with customers amid fierce competition from rival restaurant operators.

Some campaigns left customers and rival marketers scratching their heads. For example, Chipotle’s June 2017 buy-one-get-one-free advertisement for nurses showed a foil-wrapped burrito “dressed” in blue scrubs and a stethoscope. The text read “Code Burrito” - leaving some viewers to think of “Code Blue” medical emergencies.

Chipotle disclosed in a January filing that it had signed retention agreements of $1 million for Chief Financial Officer Jack Hartung and $600,000 for Crumpacker that would reward them for staying one year after a new CEO was appointed.

A Chipotle spokesman said Crumpacker will receive previously negotiated post-employment payments, including his retention bonus.

Hartung’s and Crumpacker’s retention agreements included several scenarios for payment upon their early departures - including reductions in duties and moving primary work locations by more than 30 miles.

Niccol took the helm from Chipotle founder Steve Ells on March 5 and is based at Chipotle’s Denver headquarters.

Ells and Crumpacker work from Chipotle’s New York office and Hartung is based in Chicago.