Rookie Shortstop Nick Ahmed‘s time in the big leagues is over for now, left-hander Andrew Chafin’s is about to begin; in a pair of twin moves, the Diamondbacks have promoted Chafin and outfielder Xavier Paul to the majors, optioning Ahmed and outfielder Roger Kieschnick to Triple-A Reno.
Chafin, 24, is 8-6 with a 3.96 ERA between Reno and Double-A Mobile this year, but there was a stark difference in his performance at the two levels. He went 4-1 with a 1.96 ERA in 55 innings for Mobile, earning Southern League All-Star honors, but since then is 4-5 with a 5.40 ERA in 76 2/3 frames for Reno.
A supplemental first round pick in 2011, Chafin was ranked by Baseball America as Arizona’s ninth overall prospect in February of 2013. That season, Chafin posted a shiny 2.89 ERA between Mobile and high-A Visalia. His peripherals, though, told a much more mediocre story (2.9 BB/9, 6.2 SO/9), and when the 2014 lists rolled around, he did not make BA’s top 10 list. MLB.com’s Jonathan Mayo, who had named him as the Diamondbacks’ 6th best prospect prior to the 2013 season, did not rank him among the team’s top 20 for 2014.
Chafin will reportedly serve as a long reliever in Arizona’s bullpen. Per the scouting report compiled by Mayo, he lives off of a low-90’s fastball with life and an above-average slider, only occasionally mixing in his slightly sub-par change-up.
For Paul, this will mark his first trip to the majors this season, but the 29 year old is already five years removed from his major league debut in 2009. He spent last season as a fourth outfielder for Cincinnati, hitting .244/.339/.402 with 7 home runs in 239 plate appearances, getting time in the corners and at DH. He signed a minor league contract with the Orioles in the offseason but was released by Baltimore last Sunday. The Diamondbacks scooped him up four days later.
In 82 Triple-A this year, Paul has hit .251/.311/.425 with twelve home runs and 57 RBIs.
Ahmed, 24, made his major league debut on June 29th, right after news hit that starting shortstop Chris Owings had been sidelined with a shoulder strain. In 16 games and 61 plate appearances with Arizona, he struggled to a .224/.254/.316 line, but his primary asset is his glove. Though the advanced metrics are notoriously unreliable in short sample sizes, Fangraphs’ UZR did rate Ahmed as an above average fielder at shortstop.
Brought over in the trade that sent Justin Upton to Atlanta, Ahmed struggled in Mobile in 2013 but was enjoying a strong season in Reno before his call-up. He had hit .324/.390/.431 with his highest walk rate (8.9%) and lowest strikeout rate (12.5%) since rookie ball. MLB.com subsequently as Arizona’s ninth best prospect in their updated standings, praising his range and arm at short.
Kieschnick, 27, was claimed off waivers from San Francisco at the start of the season and since then,has been up and down between the majors and Triple-A non-stop. Overall, he has amassed just 41 at bats, over which he has hit .195 with no walks, one home run and one double.