From BR Bullpen
- Bats Right, Throws Right
- Height 6' 0", Weight 160 lb.
- High School Liceo Sorana Nolan High School
- Debut September 8, 2010
 Biographical Information
Ciriaco was signed by Arizona Diamondbacks scout Junior Noboa at age 17. He made his pro debut with the 2003 DSL Diamondbacks, hitting .231/.290/.294. He returned to the same club in 2004, hitting .349/.401/.437. He was fourth in the Dominican Summer League in average and led his team in six offensive categories.
Coming stateside in 2005 with the Missoula Osprey, Pedro fell to .240/.264/.331. His 34 errors led the Pioneer League's shortstops and he fielded .899. With the 2006 South Bend Silver Hawks, he improved to .264/.308/.320 and scored 77 runs with 19 steals in 27 tries. His fielding improved to .927 but he still made 45 errors. He led all of the minor leagues in miscues on defense.
Baseball America rated Pedro as possessing the top infield arm in the Arizona organization entering 2007. That year, his line was .251/.286/.322 for the Visalia Oaks. He cut his error total to 32 and raised his fielding percentage to .938. He led California League shortstops in errors.
Returning to Visalia in 2008, Ciricao made major strides, hitting .310/.333/.408 with 40 steals in 49 tries, 85 runs and a .949 fielding at short (23 total errors). His biggest problem was walks, as he drew only 18 in 124 games. He tied Mike Paulk for sixth in the California League in average and was third in hits (161, 25 behind Cedric Hunter) and steals (10 behind Peter Bourjos). He led Diamondbacks minor leaguers in swipes. He made the Cal League All-Star team in short. For the first time in his four US seasons, he did not lead his loop in miscues; he had fewer than half leader Marcus Lemon's total at SS.
Baseball America rated him as the best defensive infielder and having the best infield arm in the Arizona organization entering 2009. He batted .296/.319/.367 for the Mobile Bay Bears with 38 stolen bases in 48 tries. He made only 17 errors and led the Southern League's shortstops in fielding percentage (.960). He was rated by Baseball America as the best defensive infielder and best infield arm in the SL. He was second in the league in steals, four behind Matt Young. He was named the SL All-Star shortstop. He had a busy winter, hitting .258 for the Scottsdale Scorpions with five swipes in 15 games then .320 for the Toros del Este.
Opening 2010 with the Reno Aces, Ciriaco was at .243/.264/.391 after 58 games while fielding .963 at short. He made the World Team for the 2010 Futures Game. Shortly thereafter, Arizona dealt him with $3 million and Chris Snyder to the Pittsburgh Pirates for D.J. Carrasco, Bobby Crosby and Ryan Church. Ciriaco was assigned to the Indianapolis Indians, where he batted .281/.288/.372 and just two walks in 32 games while fielding .931 at SS.
A September call-up to the majors, Pedro joined fellow 2010 Pirates shortstops Ronny Cedeno and Argenis Diaz (both of whom had also joined the organization in trades, only a year prior). Ciriaco made his MLB debut as a pinch-hitter for Chan-ho Park. Facing Cristhian Martinez, Pedro doubled in fellow rookie Pedro Alvarez. He later scored on a hit by another September call-up, Brandon Moss.
- 2010 Diamondbacks Media Guide
- 2005-2010 Baseball Almanacs