NEW YORK ( TheStreet) -- Morgan Stanley ( MS) has hired former Goldman Sachs ( GS) partner Glenn Hadden to run its global interest rate trading business, according to an internal Morgan Stanley memo reviewed by TheStreet. Departing the firm is David Moore, Morgan Stanley's head of structured rates, according to a person with knowledge of the matter. CNBC first reported the moves. The role being assumed by Hadden is newly created, and is not similar to the one Moore had filled, the person says. Nonetheless, Morgan Stanley has been overhauling its fixed income trading operations in the wake of disappointing performance. Jack DiMaio had been global head of interest rate credit and currency trading at Morgan Stanley left a few days ago, just 18 months after he was brought in to revive risk-taking at a division. However, results under DiMaio were still unspectacular, according to published reports. Morgan Stanley, which reported fourth quarter earnings Thursday, saw its "core" fixed income trading drop 38% versus the third quarter, according to a report from Sandler O'Neill analyst Jeff Harte. Harte wrote that the fixed income trading results were "even weaker than we expected." Hadden was the subject of a brief item in The Wall Street Journal in August, which noted his disappearance from Goldman, calling it "one of the enduring mysteries of the credit crunch." The story stated that he had been on paid leave of absence since late 2009. Hadden could not be reached. Goldman spokesman wrote via email that he "retired" at the end of last year. A Morgan Stanley spokesman declined comment. -- Written by Dan Freed in New York.