Newton's Third Law, baseball-style

For every action, there is an equal and opposite reaction.

So sayeth the RedSox:

The Yankees' recent purchases can only be further motivation for the Boston club. The American League East was typically one of baseball's toughest divisions. And that was before the emergence of the Rays, who went from nowhere to the World Series in one season and now cannot fairly be expected to return to oblivion.

The Red Sox, having finally gained the upper hand in the rivalry with the Yankees by the virtue of two World Series championships in the last five seasons, cannot sit idly by and watch the Yanks make dramatic, if incredibly expensive, improvements. And that is what the acquisitions of Sabathia and Burnett were. The Yankees have not won a World Series since 2000, primarily because their starting pitching wasn't of championship caliber. On paper, at least, that shortcoming has now been directly addressed.