The NL roster for the All-Star Game currently consists of 20 everyday players and 13 pitchers.
Going purely on total 2013 Wins Above Replacement (Baseball-reference version) for everyday players, 13 of those 20 everyday players are also in the top 20 in WAR among NL everday players this season: Molina and Posey at catcher, Goldschmidt and Votto at first, Matt Carpenter at second, Wright at third, Tulowitzki, Cabrera and Segura at short, and in the outfield the Carloses Gomez and Gonzalez, Domonic Brown and Andrew McCutchen.
Missing from the actual roster but in the top 20 in WAR are:
–Starling Marte, sixth in the NL in everyday player WAR but both a newcomer and an all-around talent with no single standout stat that grabs popular attention.
–Russell Martin, another Pirate, much of whose WAR this season is coming from his defense (throwing out an excellent 50% of base stealers this season), which has not previously been considered a big strong point for him.
–Gerardo Parra, who with Carlos Gomez and Marte make up the top 3 NL outfielders in fielding WAR this season.
–Andrelton Simmons, WAR’s most valuable defensive player in the majors so far this season
–Jay Bruce, phee-nom Yasiel Puig and Ian Desmond are currently 18th, 19th and 20th in NL everyday player WAR. Despite his short time in the majors, WAR finds Puig as having been more valuable so far this season than All-Star outfielders Carlos Beltran, Bryce Harper and Michael Cuddyer. Puig may still make it as the fan-elected final selection to the All-Star roster.
One problem for All-Star roster constructors is the dearth of qualified third basemen in the NL this season beyond David Wright. Pedro Alvarez is on the roster, and is probably as good a pick as any for backup at third, but he is way down the list in terms of overall WAR. A WAR-maximizing strategy might be to use Matt Carpenter at third, where has played quite a bit, but Carpenter clearly deserves to start at second, and the WAR alternatives at second base aren’t especially impressive either.