Bob Melvin uses the scrubs when they're in a game down several runs late, which has led to a lot of blowout losses (the main reason their run differential is so bad). From Melvin's perspective, if he brings in a reliever to pitch in a situation where it's teetering on the brink of a blowout, and he gives up runs, that pitcher's going to stay out there to at least eat up some innings to save his better relievers for another day, no matter how bad they are pitching. The Dbacks scrub relievers probably have zero confidence because of it, but at least they know that they have a role, and will continue to get opportunities to pitch, and pitch well. What a concept. Bob Melvin is an example of a good manager. Like other posters have said, defense and pitching are the key reasons. The manager and Brian Anderson are the intangibles.