To no one's surprise, the starting catcher for the Arizona Diamondbacks All-Stars is 2012 Miguel Montero, with 59% of the vote (155 votes total.) 2000 Damian Miller and 2015 Welington Castillo combined for 35% of the vote, with 2008 Chris Snyder and 1998 Kelly Stinnett getting a small number of votes each.
Keep in mind, for the remainder of this paragraph, that Fangraphs doesn't like Paul Goldschmidt as much as does Baseball-Reference. For example, last year, Goldy was only worth 7.4 fWAR, as opposed to 8.8 bWAR. And still, he owns the three best seasons in franchise history at first base by fWAR, as well as the sixth best, giving him four of the top six, all time. The best was 2015, 1.2 wins better than his 2013 season. The third best season in franchise history was his injury shortened 2014, where he was worth 4.4 fWAR. Basically, in addition to being vastly superior in raw numbers, Goldy's 2015 was 3.5 fWAR better than the next person on the list. His 2015 was the type of season that, if he has four or five more, will get him into Cooperstown. .321 batting average. .435 on-base percentage. 33 home runs, and 21 stolen bases. His walk rate was the second-highest in franchise history at first base (minimum 200 plate appearances) and his ISO third (both to Erubiel Durazo, who does not appear elsewhere on this list thanks to not getting enough playing time, platooning as he did with Mark Grace. His OBP was the highest by a first baseman in franchise history, and his .570 SLG trailed only Tony Clark's 2005.
So Goldy being the best first baseman, and 2015 being his best season, there's no need to vote for a starter. Instead, let's vote for a backup. Here are the next five on the list.
Tony Clark, 2005
One big surprise is that there are two candidates from 2005 on this list. More surprising, the fourth and fifth best seasons at first base in team history (minimum 200 plate appearances) were both in that same year. If you combine Tony Clark and Chad Tracy, you get 7 fWAR, which would be good for second in franchise history. Tracy saw action in the outfield that year as well. Clark only played first base and DH, and put together a career year. His OPS of 1.003 shattered his previous career high of .880. He hit over .300 for the only time in his career. Similar to Goldy, DRS liked his defense and UZR did not, which gave him 3.3 bWAR and only 3.1 fWAR. Clark was also worth 2.2 WAA, surpassing Tracy in that statistic.
Greg Colbrunn, 2000
Here's a name I didn't expect to see posting the ninth-best season by a first baseman in franchise history. Colbrunn hit for average in 2000, posting a .313 average that has only been surpassed by a Diamondback first baseman twice since (and Carlos Baerga in 2003 probably shouldn't count, making it unsurpassed until Goldy in 2015.) Colbrunn would have a better offensive year in 2002, but it was 2000 where he held down first base for 116 games. Colbrunn was essentially Goldy-very-lite: good average, decent power, above-average defense, solid baserunning. His stats look a lot better now (especially his OBP) than they did in the steroid-era.
Mark Grace, 2001
By the time he arrived in Arizona, Gracie's career was on the downhill side. But the downhill side of a career that had seen him post 7 seasons in the top-ten for OBP and 8 in the top-ten for batting average was still really good. 2001 was his last year as a full-time starter, as he would platoon with Erubiel Durazo in 2002 and back him up in 2003. But he made the most of his one season, slashing .298/.386/.466 for an OPS+ of 113. He had the lowest K-rate of any first baseman in franchise history, at 6.5%. He followed that up with a postseason to remember, going 6-for-16 in the NLCS, and 5-for-19 in the World Series, including a home run. But it was his single in his final World Series at bat which proved key, leading off the bottom of the ninth against Mariano Rivera. Fangraphs gives him 2.6 WAR for 2001, Baseball-Reference 2.4. As far as a full career is concerned, Gracie has the best of any Diamondback first baseman ever (although Goldy has a very excellent chance of catching him.) Is his 2001 good enough to justify selecting him to back-up Goldy's 2015?
Conor Jackson, 2008
Prior to Goldy's arrival in 2011, it seems like the Diamondbacks had bad luck with their first basemen. Travis Lee never lived up to his potential, Erubiel Durazo was injury-prone, but the worst luck of all belonged to Jackson. At 26, he had a breakout season in 2008, hitting .300, slugging .446, and playing solid defense with good baserunning. He looked set to develop into a solid 3 win player. Season highlights for Jackson included an opportunity to hit for the cycle, finishing a double short (having tripled in this last at-bat.) Jackson didn't strike out much, only in 10% of plate appearances. Sure, he could have stood to walk more (only 9.6% of plate appearances) but he was a tough out every time he was at the plate, showed power, and even showed some speed (10 stolen bases.) Of course, he did play more in the outfield in 2008 than he did at first base, but he spent plenty of time at first base to qualify for the purposes of this article (200 plate appearances.) He also won NL player of the week twice in 2008. Sadly, his career was derailed with his bout with Valley Fever starting in 2009, and he would never be the same player again.
Chad Tracy, 2005
The other half of the 2005 first base platoon (which also makes this article a 2005 first base sandwich, thanks to their positions on opposite ends of the alphabet) put together 3.9 fWAR, the most by any first baseman not named Goldschmidt in Diamondback history. He played just over half of his time at first, though, spending plenty of time in right field and a bit in left. Tracy posted a career high OPS+ (132) along with an ISO of .245. He hit 27 home runs (a career high.) The thing that hurts his candidacy the most is that those numbers were surpassed by Tony Clark in the same year. I remember thinking that Tracy was going to go on to be a big star for the Diamondbacks (putting up 3.6 bWAR and 3.9 fWAR at 25 will do that) but this was the high point. Still, his 2005 ranks as the 23rd best in Diamondbacks history (all positions, minimum 200 plate appearances.)
Two additional questions
Since I've decided to have back-ups as well as starters, should I follow typical All-Star protocol and include a member of each Diamondback team ever? Also, should I separate outfield positions or have them combined? Let me know in the comments.