With just two months left in the regular season, baseball's contenders are attempting to shore up their rosters by Tuesday's trade deadline. But that number is quickly dwindling in the National League.

The Cubs, Padres, Rockies and Astros are hopelessly out of it. Those teams have been rebuilding for weeks. The Phillies, now 12? games out of a playoff spot entering play Monday night, come to town to face the Nationals this week far more likely to trade away key players than to add one. Just ahead of them in the standings, the Brewers (Zack Greinke) and Marlins (Hanley Ramirez) have already conceded after trading away top stars. The Mets lost 13 of their first 16 games to start the second half and are fading fast.

That leaves three teams with realistic hopes to catch Pittsburgh or Atlanta for the two NL wild-card berths -- or, if their small division leads don't hold up, the Nationals in the East or Cincinnati in the Central. So far, neither Arizona nor St. Louis has made a major move. The Diamondbacks added Chris Johnson from the Astros for a modest upgrade at third base. The Cardinals have the best run differential in the entire league (plus-94) -- yes, better even than Washington (plus-82) -- and might not need anything other than better luck.

Meanwhile, both the Dodgers and the Giants are in an arms race in the NL West, with the loser left pushing for the wild card. Los Angeles snatched Ramirez from Miami hoping he finds his swing. There has been nothing on the trade front from San Francisco so far, but it probably can't afford to stand pat much longer.

- Brian McNally