Steve Berexa has been appointed as manager of the £103.8m Allianz US Equity fund after former manager Seung Minn left the firm.
Under Mr Minn the fund had slipped to the bottom quartile of the IMA North America sector for performance in both one and three years.
Mr Berexa is head of global research at Allianz, having joined the firm in 1997 from Prudential.
Allianz said that “the investment philosophy and process of the strategy will remain the same” under Mr Berexa.
The firm said Kim Millar and Shibin Xie will remain as analysts on the US team, reporting to Mr Berexa, and that a co-manager for Mr Berexa will be appointed soon.
Morningstar has placed its bronze rating on the fund under review following the departure of Mr Minn last week.