The toughest June for retailers since 1986 has taken its toll on JJB Sports, as a slide in sales prompted a profit warning and questions over to what extent the much-vaunted recovery strategy would help it see off a protracted downturn.

The deteriorating outlook led Panmure Gordon, the sportswear retailer’s broker, to cut its pre-tax profit forecast for the year by 19 per cent, after like-for-like store sales in the 12 weeks to last Sunday slid 2 per cent.