One important thing to keep in mind as the Nationals look for a new pitcher is that they are replacing Edwin Jackson. The Nationals are looking for a fifth starter and now as the market is starting to develop the players the market views as such can be identified. There is a lot of talk about Zack Greinke who everyone knew was going to be highly sought after and then the second tier guys are not the ones that were expected. Kyle Lohse and Anibal Sanchez are emerging as the two options after Greinke.
Before the off-season began it was my estimation that Ryan Dempster would be the most overpaid player on the market, but that isn't coming to fruition. The only team that has been reported with any level of interest are the Twins, but that may be due to the fact that options for Dempster won't be fully realized until Greinke, Lohse, and Sanchez have signed. It is then that the market for Dempster would start to materialize.
Since returning to a role as a starter in 2008 Dempster only failed to pitch 200 innings once and that was this past season. Combine that with the fact that he will be entering his age 36 season and it might cause some clubs to be weary of him. Dempster also could be viewed as an NL only pitcher his 5.09 ERA in 12 starts with the Rangers in 2012 certainly won't help an AL team to decide to sign him.
When it comes to what Dempster would add to the Nationals it isn't much. He and Edwin Jackson are both consistently around the 2.5 to 4.0 WAR range over the past several seasons. It can be reasoned that the production the Nationals would get from Jackson can be equaled by Dempster. The question is then what will Dempster cost.
Both the Dodgers and the Nationals were thought to be interested in Dempster around the trade deadline. Dempster turned down a deal that would have sent him to the Atlanta Braves around the trading deadline because it was thought he wanted to pitch for the Dodgers. He instead ended up on the Rangers, but his interest in the Dodgers could still remain and if the Dodgers miss out on Greinke they have shown a willingness to overpay for mediocre talent.
Ryan Dempster is not a player that should get a long term contract. He should get a one or two year deal in the range of $20-$25 million. What he will get though will be determined by what the market is willing to pay him. At this point it doesn't look like there are a lot of teams interested in going out and getting Ryan Dempster which works into the hands of the Nationals. The Nationals have the pitching depth to be able to wait out the market and let a player like Dempster fall to them much like they did last off-season with Edwin Jackson.
Dempster wouldn't be much of an improvement on Edwin Jackson, but he wouldn't a drop off either. They are very comparable pitchers with Dempster being the more consistent of the two while Jackson has the ability to throw a gem or a disaster every now and again. Dempster would also allow the Nationals to jettison John Lannan with no worries that he will be needed while they wait for Alex Meyer to develop.
Dempster is an interesting solution that may fall to the Nationals, but the Nationals should in no way put themselves into the market for Dempster. If it does come to them they should not be afraid to pounce.