The Athletics enter Wednesday at 18-17, just a game over .500, and yet two games above the Seattle Mariners in the AL West. In nearly every other division, they'd be operating at a good-sized deficit of at least four games, but the A's find themselves in the spot they want to be for the whole year. While it's still considered early and standings hold more weight after Memorial Day, the green and gold need to make sure that they're putting out the best roster possible on a nightly basis. On Tuesday night in the series opener with the Philadelphia Phillies , Luis Severino kept the game close for five innings, Scott Barlow added a scoreless sixth inning, and then Mark Leiter Jr. and Tyler Ferguson allowed four runs each in the final two frames. The Phillies won by a final of 9-1, despite the game being tight until the seventh. Leiter holds a 7.98 ERA right now and hasn't gone more than four outings without allowing at least a run to score.…