World Cup winner Ali Williams warns over southern hemisphere exodus

• The former All Black worried about impact on Test rugby• Toulon eyeing up a third successive European Cup final • Owen Farrell hopes to be fit for Saracens’ semi-finalAli Williams, a World Cup winner with New Zealand who is one of Toulon’s foreign legion, is concerned that international rugby will suffer if the player drain from the southern hemisphere continues to gather pace.Williams, who is 34 at the end of the month, joined Toulon two seasons ago at the end of his international career but this week his compatriot, the 27-year-old outside-half Colin Slade, signed a two-year contract with …