Dempster is in the midst of a career year, boasting a league-best ERA at 2.11 and an impressive WHIP at 1.051. Those marks would both stand as career bests for Dempster, who's currently in his 15th season. Even with the current string of success, though, it's hard to imagine Dempster being a game-changer. He's a nice addition, yes, but his solid 15 starts this year seem to mask the fact that he's merely an above average pitcher.
The use of the term "merely" is because Dempster has suddenly been given more credit than he probably deserves. He's wheeling and dealing this season, no doubt, but giving up a valuable prospect for a 35-year-old that could turn out to be just a rental is always a risky investment, even if it helps address a major need.
The Braves did have a major need. They currently sit 27th in the bigs in quality starts, 20th in WHIP, and clearly don't feature a daunting rotation by any stretch of the imagination. Tim Hudson is generally a reliable starter, but beyond him there's some question marks, especially since Brandon Beachy went down earlier this season.
With all of that considered, the Dempster deal not only makes plenty of sense for Atlanta, but it was quite necessary. It was hard to imagine the Braves playing into October with the rotation as it's constructed, even though stranger things have happened. Somewhere along the line, they were going to have to add a piece, and Dempster is a formidable one at that.
Nothing changes the fact that Dempster is unlikely to put the Braves over the top for a number of reasons, the most glaring of which is what stands in front of them. The Nationals' rotation is far superior to the Braves', and Dempster hardly changes matters, even if he closes the gap.
That's essentially what this move amounts to: closing the gap. That's all fine and good, but Braves fans would be wise to temper their expectations. Dempster or no Dempster, the NL East is Washington's to lose.