Options for the 25th Roster Spot
In 2013 in the NL the average team used 45 players to make it through the season. That is nearly an entire extra 25 man roster needed to survive the 162 game baseball season. With that fact in mind it is clear that depth is hugely important to major league baseball teams. The Nats made a number of minor league signings in the off-season and prospects like Souza, Walters, Skole, and Goodwin have shown in Spring Training that they could help the big club if needed at some point during the season. The 2014 Nationals are going to have better depth than the 2013 vintage, but depth doesn't have to be used only in case of injury or under performance.
The good thing about players like Souza, Walters, and Kobernus is that they have options. With the Nationals front four starting pitchers more than likely averaging close to 6.3-6.5 innings a game and the ability to have multiple multi-inning relievers in the bullpen the Nationals could fluctuate between carrying a seventh reliever as the 25th man and a sixth bench bat. Mike Rizzo and Matt Williams could get together before each month an decide how best to construct the roster. If for example we look at April we can see that the Nationals have three off days on the 1st, 7th, and 28th. That isn't a lot of off days and the Nationals do have to play the Braves and Cardinals, but they also play the Marlins, Mets, Padres, and Astros with the Angels as a kind of swing team in there that could be either good or bad. As far as April goes with the starting staff not fully stretched out and the lack of off-days the Nats could use that seventh reliever when the season starts.
In May the Nationals play once on a Thursday. Factoring in the April 28 off-day and from April 29 to May 16 the Nats play no more than six games in a week. With those built in off days in there the Nats don't need a seventh reliever during that stretch and would benefit by carrying an extra bench bat. Whether that is the switch hitting power hitting Walters, the do everything five tool Souza, a speedster like Kobernus or Perez to be a late inning pinch runner, or someone else depends on how they are performing in the minors up until that point in the season. Having an extra hitter, runner, or defender off the bench during that stretch would give the Nationals more of an advantage than carrying a seventh reliever when there are no more than six games in a row. The combination of the Nationals starting staff and the schedule will keep a six man bullpen fresh for that stretch.
Those are just a couple of examples from early in the season where different roster constructing would benefit the Nationals depending upon the schedule. The opponent is also going to have something to do with who the Nationals want on the roster. Late in the season in August the Nationals have a stretch of games against their division rival Phillies, Mets, Braves, and Mets between Ike Davis, Chase Utley, Ryan Howard, Domonic Brown, Freddie Freeman, and Jason Heyward the Nats have to deal with a lot of left handed hitters and this is a point where they may want to carry a second left handed pitcher that is more match-up oriented than Jerry Blevins. If Mike Gonzalez isn't on the roster by August he has probably used his opt out, but the Nationals will have Cedeno, Solis, and Purke available to call-up to serve as a lefty specialist at this point in the season and for this stretch of games using the final roster spot for that type of player would be the most beneficial.
The great thing about a 25 man roster is that it has flexibility. Depth isn't all about replacing injured or under performing players. It is also about analyzing the schedule and putting the best roster possible on the field on a nightly basis. If the Nationals are approaching a stretch where they have a good number of off days and can afford to only carry six relievers in favor of an extra bench guy then by all rights they should. If on the other hand they have a lot of back to back games and are going to need seven relievers they should use that roster construction. And if the opponent dictates that a match-up pitcher or platoon position player would be a benefit to the Nationals then the 25th spot on the roster should be occupied by that type of player. The Nationals have both relievers and bench players that have options and they should use those options to consistently put the best 25 man roster possible on the field on any given night.