The resignation of Wharrier marked a “notable loss” to the fund according to Morningstar analysts who dropped the fund’s bronze rating to a neutral.
They added they will continue to monitor its performance going forward under co-managers Adam Avigdori and David Goldman, who remain with the fund.
There are no plans to replace Wharrier who left BlackRock to join Troy Asset Management on 5 July after four years leading the UK equity income team, and investors have been reassured they should not see any change to the fund’s strategy.
However Peter Brunt, a senior analyst in Morningstar’s manager research team, said Wharrier had promoted a “collegial approach” between the fund’s three co-managers and was a big loss to the team.
Brunt said: “Wharrier brought structure to the investment approach and ensured that there was balance across the three co-managers.
“We consider his exit as a loss to the fund and, while we will be monitoring the progress of the Avigdori and Goldman closely, for now our level of conviction has diminished. The Morningstar analyst rating is therefore lowered to neutral.”
BlackRock said the current investment objective and guidelines of the fund would not be affected by Wharrier's exit.
In a letter to reassure clients, the firm said the fund's managers would still be able to draw on the 15-strong UK equity team and added: "Given the significant breadth and depth of the team’s resources, we will not be seeking to appoint a further co-manager on the fund to replace Mark.
"We are confident that our collaborative, team-based approach will help this to be a seamless transition."