For this article, we will discuss only those players who received their first call-ups to the majors in September, excluding those who were returning from a previous stint with the team.
1998: Neil Weber and Vladimir Nunez
Both men made their debuts in the same game, pitching mop-up in a 13-1 hammering at the hands of the Reds in Cincinnati. Clint Sodowsky and Chris Michalak had staked the home team to a nine-run lead after four. Weber worked a scoreless fifth, and Nunez a scoreless sixth, but then allowed a double and a walk in the seventh, both later scoring on a three-run homer off Alan Embree. Weber appeared in just three more major-league games, but Nunez's career lasted through 2009, though was pretty much replacement-level.
1999: Rod Barajas
Called up to provide a third catcher, behind Damian Miller and Kelly Stinnett, he didn't appear until the 154th game of the season, then started five of the last nine as we rested players for the post-season. He did the same the following September, but became a more regular back-up for the team from 2001-03, including a start in Game 5 of the World Series. After leaving the desert, he had a solid career as a starting catcher, mostly with Texas and Toronto, and finishing only last year with the Pirates.
2001: Eric Knott, Mike Koplove, Lyle Overbay, Jack Cust and Ken Huckaby
It's interesting that we called up so many players that September, as we weren't exactly cruising to the title. We entered the month with only five games separating us and the third-place Dodgers, with the Giants also in the mix. Koplove saw the most action, working nine games down the stretch, while Knott started Game 162 - the only start of his career - allowing zero earned runs...but eight unearned ones! The three position players combined for just six PAs that year. Cust went on to lead the AL three times in strikeouts, but Overbay is the oldest September call-up for us still playing, currently with the Yankees and has had the best career, with 17.7 bWAR (Cust is third, at 9.1)
2004: Josh Kroeger and Mike Gosling
With all due respect to Kroeger, looking at the D-backs line-up for his debut, it's not hard to see how we lost 111 games that year. He was heavily used, appearing in 22 games after his debut on September 2, but hit .167 and didn't trouble the major-leagues again. He is still playing however: he has over 900 games of Triple-A experience, and this season is with the Somerset Patriots of the indie Atlantic League. Gosling started four games and worked relief in another two, and hung around on the fringes of the majors with the Reds and Indians until 2009.
2005: Dustin Nippert
Nippert spot-started three games for us down the stretch, winning his last with five innings of one-hit (but five-walk) ball in Los Angeles. He had a couple more spot starts in 2006, and worked long-relief for much of the 2007 season, appearing in 36 games, plus a couple in the NL Championship Series against the Rockies. He was dealt to the Rangers for Jose Marte, who never amounted to much - but then, neither did Nippert, despite an appearance in the 2010 ALDS against the Rays, allowing two runs in an inning.
2006: Miguel Montero and Doug Slaten
Miggy is the only one of our September call-ups ever to become an All-Star, and his career bWAR of 12.5 trails only Overbay's. You probably wouldn't have predicted it from his debut, where Montero went 0-for-3 in a game which is now much more remembered for another reason - Anibal Sanchez of the Marlins no-hit the D-backs that day. Slaten had showed up a couple of days previously, and didn't allow a run in his first 18 major-league appearances, a franchise record that stood until fellow LOOGY Joe Paterson went one longer in 2011. Slaten apparently signed with the SK Wyverns in Korea for this year, but dropped out for undisclosed "personal reasons."
2007: Emilio Bonifacio and Bill Murphy
Bonifacio came on as a pinch-runner, one of three D-backs to make their debut that way without staying in the game (the others being Junior Spivey and Tyler Graham). Bonifacio ran for Chris Snyder with one out in the bottom of the eighth, down by one. He made it to third on a Conor Jackson single, but was stranded there. He is pretty speedy - 31st on the active list for stolen-bases - but that's about it, and is one of three active players with 100+ SB and 10 or fewer career homers. We have a soft-spot for Murphy as the first player we ever interviewed, but that didn't seem to help his MLB career, which lasted eight games outside of this September call-up.
2008: Josh Whitesell
I kinda thought we were the ones who had drafted Whitesell, but turns out he was actually a Nationals' pick, whom we picked up off waivers in March 2008. He got his call-up in September, after hitting .328 with 26 homers for Tucson, and was a back-up from May through August the following year, after Tony Clark hit the DL. But he never really seemed to stick, hitting below the Uecker Line. Played in the Nationals minor-league system for a bit: is currently in Japan with Chiba Lotte.
I almost included Kevin Mulvey, who made his NL debut in September that year, but turns out he had already played that season, for the Minnesota Twins. Remember Jon Rauch? Mulvey was the PTBNL when we sent him to Minnesota in August 2009. This trade was immediately a win for us, simply on the basis of Mulvey not being Jon Rauch.
2010: Zach Kroenke and Konrad Schmidt
Must have been short of K's this September. Kroenke got the gift of a relief appearance in Coors for his debut, and allowed six hits in 1.1 innings of work. Schmidt occupied the third catcher spot, behind Montero and John Hester, who took over as backup after Chris Snyder was traded. Schmidt would reappear two years later, playing in another four games, and is now with the Reds minor-league organization, probably awaiting the call-up for another four games in September 2014.
2011: Jarrod Parker
Ah, Kevin Towers - you're just such a tease.... You show us just a hint of Parker, only to send him off to Oakland, never to be heard from again [well, you know what I mean]. Certainly, his debut was memorable, though like Montero's, more for other reasons. This went into extras, Micah Owings allowed five in the tenth, only for Arizona to get six two-run in the bottom half, capped off by Ryan Roberts' walk-off grand-slam, the second such in team history [the first was by Damian Miller, off Orel Hershiser in 2000]. Yeah, if you're only going to appear in one D-backs game, that wasn't a bad one to pick...
2012: Adam Eaton and Tyler Graham
Eaton needs little introduction, but Graham gets my vote for the "Who's he?" of the 2012 Diamondbacks, as the player you're most likely to forget was part of the roster. He was basically Tony Campana v0.1: 60 SB in the minors the years before, and his ten games for the D-backs last season resulted in two (count 'em!) trips to the plate. The odd thing is, he only attempted one stolen-base in his time here, and was caught. This season, Graham has been particularly nomadic, appearing for York of the Atlantic League (wonder if he saw Josh Kroeger?), Fargo-Moorhead and Winnipeg of the American Association, and also Veracruz in Mexico.
I guess what the above tells us is that players called up in September tend not to amount to much. That's a total of 21 in team history, the majority of whom have had major-league careers barely above replacement-level. There is some logic to this: if they were "good enough" for the majors, why weren't they called up earlier? It's unlikely they improved a lot on September 1. Of course, there are occasionally legitimate reasons i.e. not starting the service time clock, as with Parker. But generally, cruel though it may be to say so, these seem more like the last cars left in the showroom than this year's models.