By Marc Normandin

It's been a hectic few weeks for the Diamondbacks. They were seen as being legitimate contenders in the National League West until a spring training injury to their nominal ace, Patrick Corbin, put a rotation that couldn't afford an injury into a precarious position. An awful start to the year further derailed hopes of competing, and now an injury to one of the only players hitting, Mark Trumbo, puts them further into a hole. Just months after receiving extensions, both general manager Kevin Towers and manager Kirk Gibson are answering questions about their job security thanks to their club falling on their faces out of the gate.

Arizona is currently 6-18, a .250 winning percentage that has them 8 games behind the first-place Dodgers despite Los Angeles only playing 22 times so far in this young season. It's not impossible to come back from a notably poor start to compete and make the playoffs, but it's a rarity. As Jay Jaffe noted at Sports Illustrated recently, no team in the wild-card era has ever made the playoffs after beginning the year 4-12, and the last non-strike team to do so was the 1951 Giants. Of note: That occurred 10 years before Towers -- who finished his playing career in the 1980s -- was born.

The D-Backs have that same winning percentage now, with six fewer games to play catch-up with. Optimism is at a low point thanks to a team ERA that sits at 5.69, with the starters responsible for much of that thanks to a 7.23 ERA and just over five innings per start on average. As a group, they're allowing opponents to bat .311/.373/.520, 48 percent worse than the average rotation gives up, they've struck out 6.92 hitters per nine while the average rotation whiffs 7.71, and their cumulative strikeout-to-walk ratio is barely above two, whereas the sport is at 2.57. They've also allowed 28 homers, the worst mark in the majors. There is very little help on the way, as they've already been tapping into their depth to get even this far.

Rewind to spring training and season preview season, and you'll find that these struggles, while worse than expected, are no surprise:

The rotation still has potential, but it has lost a step with Corbin's exit. Wade Miley, who is good but not overpowering, is likely the D-Backs' top starter now, and they're relying on a trio of disappointing 2013 arms to recover and make this rotation relevant again: Brandon McCarthy (84 ERA+ in 22 starts), Trevor Cahill (96 ERA+ and 146 innings after a superior and promising 2012) and Randall Delgado, who wouldn't even be in the rotation if not for Corbin's season-ending surgery. They also need free-agent acquisition Bronson Arroyo, who was signed almost entirely because of his durability, to overcome the back woes that have limited him this spring.

Miley is currently a ground ball pitcher giving up homers who has walked nearly four batters per nine. Cahill is already out of the rotation after making just four starts: while he's missing bats, with more than a strikeout per inning, he has walked more than five per nine and possesses a 48 ERA+. McCarthy hasn't been much better: While he has averaged six innings per start, he has also given up seven homers and owns a 6.23 ERA to this point. Arroyo has made four starts totaling just 18 innings, and has the worst ERA+ on the team at 38 -- it's possible he's not entirely over the back problems that caused him to miss time during camp.

The Diamondbacks have already used seven different starting pitchers this year, including Josh Collmenter, who was pushed out of the rotation and into a relief role just two years ago, and Michael Bolsinger, which isn't a name we just made up. They still have prospect Archie Bradley in the minors, and he could be up at some point this season, but he's just one arm, and the Diamondbacks might need to overhaul their entire rotation to get back on track this year. If the arms already in place can't turn things around, it's going to reflect poorly on a front office that traded both Tyler Skaggs and Ian Kennedy in the last year.

Skaggs was part of the Trumbo deal, and while that can certainly still end in the Diamondbacks' favor, a stress fracture in his left foot will put that on hold for now. Trumbo was third in the majors in homers with seven, even though he was batting just .210 on the season, thanks in part to his being freed from pitcher-friendly Angel Stadium. The 28-year-old leftfielder had been one of the only D-Backs hitting, as his OPS+ of 109 was one of just three from the regulars that was above the league average. Now, first baseman Paul Goldschmidt (148) and catcher Miguel Montero (110) are alone in that regard.

Shortstop Chris Owings has been doing well enough, especially for the position, as he's batting .294/.351/.338. After that, though, is sadness: A.J. Pollock (78 OPS+), Gerardo Parra (73), Martin Prado (67) and Aaron Hill (63) have all been a drag on an offense that can't afford to be lagging behind given the horrendous pitching on display all month. All of these hitters -- especially Prado and Hill -- are far better than this, and their horrible start is likely a temporary state, but each day that they don't hit is spent digging a deeper hole the D-Backs won't be able to climb out of.

Trumbo is getting a second opinion, so it's possible he doesn't end up missing all that much time. Hill and Prado should rebound, and while Parra and Pollock aren't juggernauts, getting closer to their position's respective averages should help. It won't be enough, though, as the rotation needs to settle in. McCarthy is capable of much better work than this, and should be at least average when he can keep the ball in the park. Cahill is out of the rotation, but he has too much talent to be overtaken by Collmenter for long. Arroyo has been inconsistent, but he's rarely outright bad, and should be able to turn things around. If Miley can get the ball on the ground with the same success he has shown in the past, his early struggles will also be forgotten.

The problem is that this is a whole lot of things that need to go not just right, but spectacularly, and soon. The Diamondbacks very well might not be bad all year long. They're coming off back-to-back 81-81 campaigns, though, didn't upgrade their team considerably in the off-season, and would still be a few games under .500 on the season even if they won every single one of their remaining April contests. Even if they rebound and play better than they have in the past two seasons from this point forward, they won't have the luxury of any other poor months, not when more NL teams might be vying for the two wild-card spots than won't.

What this means for Towers and Gibson is unknown, but with all of the roster shuffling, shipping out of young talent and prospects, and no improvements coming on the major-league side, it's going to be difficult to argue in their favor for much longer if things don't take a turn for the better soon.

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Marc Normandin writes and edits for Over the Monster, a Boston Red Sox blog, as well as SB Nation's baseball hub. He's one of many behind the e-book "The Hall of Nearly Great," and has written for BaseballProspectus, ESPN, and others. You can follow him on Twitter at @Marc_Normandin