A big market city, such as Boston, comes with big payrolls and even bigger expectations.

Year after year the front office, coaches and fans expect a certain level of excellence from their players. If they do not live up to their potential then it’s the general manager’s job to find someone who can.

It used to be that most players, especially stars, would start and finish their careers in the same uniform. However, since the introduction of free agency that is now rarely the case.

Players on small market clubs are often the subject of trade rumors as their contract nears free agency to ensure their current teams gets value in return for their inevitable departure.

Such was the case this offseason when the Padres shipped Adrian Gonzalez to the Red Sox in exchange for a collection of prospects.

Other times general managers have to address team needs in an attempt to build a roster that has a realistic shot at a World Series Championship. Theo Epstein went this route in what many baseball minds would consider the most controversial and talked about trade in Red Sox history.

In an effort to originally reverse the curse, and since to remain a top power in baseball, the Red Sox have made several significant and brash deals since the turn of the millennium.

Here is how all those deals stack up in a ranking of the ten most important trades the Boston Red Sox have made since 2000.

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