Now that the Masahiro Tanaka sweepstakes are officially under way, key details relative to his negotiations with potential MLB suitors are starting to come out. The first major one, as initially reported by Japanese media outlets and confirmed by Joel Sherman, is that he has chosen Casey Close as his agent. From the Yankees' perspective, this has to be seen as another bit of good news and an advantage for them in the negotiating process.
Close, you'll recall, is the agent for current Yankees Derek Jeter and Mark Teixeira and he was instrumental both in getting Jeter his big 10-year deal in the 2000 offseason and in working out Jeter's new 1-year deal with Hal Steinbrenner. He doesn't have any experience with major international free agents from what I've read, but he's got a very good history in working out big money deals for other MLB players.
The Yankees already held a number of competitive advantages over the field when it came to signing Tanaka. They've scouted him more extensively over the last year plus than any other team, they have the most money to spend on him regardless of posting rules, they have a gigantic media market with a history of being good to premiere Japanese players (some of whom are still on the Yankees right now), and they have a huge need for rotation help that makes their expansive monetary resources even more potentially imposing. Add Close and his Yankee ties to the mix and that has to qualify as another advantage Yankees.