From BR Bullpen
David Shelley Duncan
- Bats Left, Throws Right
- Height 6' 5", Weight 215 lb.
- School University of Arizona
- High School Canyon del Oro High School
- Debut July 20, 2007
- Last Game April 27, 2013
- Born September 29, 1979 in Tucson, AZ USA
 Biographical Information
Duncan hit .294 as a college freshman at the University of Arizona but slugged .640 with 20 home rusn and 68 RBI. Baseball America named him a freshman All-American first team outfielder. He hit .338 and slugged .638 as a sophomore. In his junior year, Duncan hit .338 once more, but with a .702 slugging percentage. He led the Pacific-10 Conference in home runs (24) and RBI (78) and his 64 runs were two shy of leader Ernie Durazo. Duncan made the All-Conference team, joining the likes of Carlos Quentin, Chris Duffy and Ben Francisco in the outfield. Both Collegiate Baseball and Baseball America chose him as a first-team All-American, though the third major source, the American Baseball Coaches Association, did not name him so highly. Duncan finished 4th in NCAA Division I in homers, 7 back of John Van Benschoten. He was drafted by the New York Yankees in the 2nd round (62nd overall) of the 2001 amateur draft. He signed on June 17, 2001 for a $655,000 bonus.
Duncan debuted professionally in 2001 with the Staten Island Yankees and hit .245/.311/.410. Moving up to the Greensboro Bats in 2002, Shelley batted .267/.375/.461 with 15 steals in 18 tries and 14 homers. In 2003, the 23-year-old was on the Tampa Yankees, producing at a .264/.336/.406 clip. Returning to Tampa in 2004, Duncan hit .248/.336/.450 with 119 strikeouts, 19 homers and 78 RBI. He finished fourth in the Florida State League in the latter two categories.
Shelley began to blossom in 2005 with the Trenton Thunder - his batting line read .240/.323/.490 and he had 86 runs, 34 home runs and 92 RBI. Downsides were 140 strikeouts and a .213 average against left-handers. He led Yankee farmhands in total bases (263), homers and RBI and was 4th in the affiliated minors in home runs behind Brandon Wood, Joe Koshansky and Brett Harper. Duncan was rated the best power prospect in the Eastern League by Baseball America, though he failed to make the publication's list of the top 20 prospects overall in the EL. Duncan led the EL in games (142), total bases and homers and tied Mike Jacobs for the lead in extra-base hits (64). He also led EL first basemen in putouts (1,178), double plays (123) and errors (16). He was named to the Eastern League post-season All-Star team.
In 2006, Duncan returned to Trenton, where he hit .256/.327/.487 with 19 HR in 92 games. He also played 12 contests with the Columbus Clippers, going 8 for 43 with 12 total bases and five walks in his AAA debut. He missed time due to an injury.
Duncan began 2007 with a bang. The tall slugger cracked 25 homers in his first 91 games with the Scranton/Wilkes-Barre Yankees to break Wendell Magee's franchise record on July 19th. He was hitting .295/.380/.577 with 79 RBI. He was leading the International League in slugging, 26 points over Mike Hessman and was second to Hessman in both homers and RBI. That earned him a promotion to New York to replace Kevin Thompson as a bench spot as one of New York's backup outfielders. Despite missing the last month-plus of the year, Duncan still was named to the IL All-Star team in the outfield, alongside Ben Francisco, Justin Ruggiano and Timo Perez.
A day after his Scranton/Wilkes-Barre home run record, he was starting in the majors, batting 9th and playing DH for the Yankees. He struck out in his two at-bats against Edwin Jackson but singled home Robinson Cano in the bottom of the 8th for his first hit and RBI. The next day, he hit his first MLB homer, a shot against Jae Kuk Ryu with Andy Phillips aboard.
Duncan became a manager with the Hillsboro Hops in 2015.
 Year-By-Year Minor League Managerial Record
|2015||Hillsboro Hops||Northwest League||45-31||1st||Arizona Diamondbacks||League Champs|
|2016||Hillsboro Hops||Northwest League||Arizona Diamondbacks|
Sources: 2000-2007 Baseball Almanacs, 2007 Yankees Media Guide