Here are some 2014 payroll AAV numbers for the Yankees:
Guaranteed deals: A-Rod, Sabathia, Tex, McCann, Jeter, Soriano, Wells - total 114 million
Arbitration eligible - Robertson, Gardner etc. - estimated total 18 million
40 man roster, benefits etc. - estimated total 22 million
That's approx. 154 million. So if they really intend to get under the 189 million, they have about 35 million allotted for Cano, the rotation etc.
Unless of course A-Rod's suspension holds up, which means it's about 63 million. Maybe they are counting on this.