Andy Pettitte takes on advisory role with Yankees, aiming to provide guidance and perspective

Pettitte signed on as an adviser for the Yankees recently after years of informal pitching advice.
He will be with the team for some games but may be away at times due to other commitments.
Pettitte hopes to lend his experience and knowledge, particularly as a sounding board for pitchers.
He was already assisting the team by watching minor league pitchers.
Yankees manager Aaron Boone praises the credibility Pettitte brings.