Martin O'Neill: Roy Keane's volatility is OK, says Giovanni Trapattoni successor as Republic of Ireland manager

Roy Keane has been appoint O'Neill number two (Getty)

Martin O'Neill believes Roy Keane's unpredictable character will be a huge asset in his new role with Republic of Ireland.

The former Manchester United captain has been appointed No 2 to manager O'Neill, who was yesterday officially unveiled in Dublin as successor to Giovanni Trapattoni. "I think he will be brilliant for the Republic of Ireland and I will want him basically the way he is," said O'Neill. "His thirst for knowledge is amazing. A little bit of volatility will do no one any harm." Keane infamously walked out on Ireland at the 2002 World Cup after falling out with Mick McCarthy.

"When I did mention the possibility of him working with me here, it took him about four and half seconds [to say yes]," O'Neill added.

The pair will meet up with the Ireland squad for the first time tomorrow evening ahead of Friday's home friendly against Latvia.