Man Group, the alternative investment manager, has appointed Dr Douglas Greenig as chief risk officer at AHL, its quantitative managed futures manager. Greenig has previously worked at RBS Greenwich Capital and Fortress over a 20 year career. Matthew Sargaison, the current chief risk officer, will become AHL's chief investment officer, where he will monitor strategies in client trading. He rejoined AHL in 2009 having worked for the firm between 1992 and 1995.