M&G Global Basics fund manager Graham French is to leave the group, Investment Week, IFAonline.co.uk's sister title, reports.
The £4.2bn fund has suffered a prolonged period of underperformance over the past 18 months and beyond, for which French apologised last month.
The manager (pictured) has run the portfolio since 2000, having been with M&G since 1989.
Exposure to the struggling commodities and mining sectors hurt returns, especially during 2012. French subsequently cut back exposure to these areas, but the fund's performance has yet to recover.
The manager said there were some days last year when he "felt like putting [my] head under a duvet and not getting up in the morning".
He added that investors wanting greater exposure to financials or technology should "look at other funds" rather than waiting for such a shift to occur in Global Basics.
M&G Global Basics has returned 3.7% over the year to 8 November, according to Morningstar, compared with an IMA Global sector average of 22.9%.
Over three years the fund has lost 0.9% compared with a sector average return of 25.8%.
M&G could not be reached for comment. It is not yet known who will be taking on the Global Basics mandate.
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