Hedge fund giant Man again needed the help of recent acquisition GLG as market uncertainty following the earthquake in Japan took its toll on its core AHL fund.Funds under management over the past three months edged up to $69bn from $68.6bn at December, though AHL's performance "turned sharply down with markets after the Japanese earthquake but has since partially recovered". A positive performance at GLG also counterbalanced a negative period for AHL, Man said.AHL's funds under management fell to $22.8bn from $23.6bn at end December, while GLG improved from $30.3bn to $32bn with all of its funds picking up. Multi-Manager dropped to $14.2bn from $14.7bn. Overall, the fourth quarter is expected to see net inflows of approximately $0.7bn, reflecting $5.3bn sales and $4.6bn redemptions.Underlying profits for the year to March will be flat at $560m, reflecting an improvement over the first half, though pre-tax profits will tumble to $280m after a $280m goodwill write down. Performance fees picked up sharply to $145m from $97m last year, though management fees fell slightly.