Morningstar OBSR has placed the BlackRock UK Income under review after co-manager Nick McLeod-Clarke announced he is taking extended sick leave.
The £625m BlackRock UK Income, which has a silver rating, is managed by McLeod-Clarke and Adam Avigdori.
Avigdori, who has co-managed the fund since November 2009, has assumed full responsibility.
The fund ratings agency says: “Morningstar OBSR acknowledges that Mr Avigdori benefits from the support of the broader UK team; furthermore BlackRock has also indicated that it is looking to add resources to support the management of the fund.
“Nonetheless Morningstar OBSR feels it prudent to place the fund under review at this time.”