Part 25 in a season-long series projecting a hypothetical 25-man roster made up solely of prospects from the Texas Rangers' Minor League system.

When Johan Santana was 18 years old, he was making his stateside Minor League debut, and he was terrible.

When Ubaldo Jimenez was 18, same thing.

The 2011 season was a disappointing one for 18-year-old right-hander David Perez, but all you need to do is look at Santana's and Jimenez's first seasons away from Latin America for reassurance that the Rangers prospect's future could still be extremely bright.

Or you could look at the season Perez had in the Dominican Republic in 2010.

Jamey Newberg's hypothetical 25-man roster made up of Rangers prospects
No. 1 starter: Martin Perez
No. 2 starter: David Perez
No. 3 starter: Neil Ramirez
No. 4 starter: Cody Buckel
No.5 starter: Luke Jackson
Long reliever: Barret Loux
Right-on-right: Johan Yan
Left-on-left: Joseph Ortiz
7th-inn. reliever: Justin Grimm
RH setup: Roman Mendez
LH setup: Robbie Ross
Closer: Tanner Scheppers
Catcher: Jorge Alfaro
First baseman: Chris Davis
Second baseman: Luis Sardinas
Shortstop: Jurickson Profar
Third baseman: Mike Olt
Left fielder: Engel Beltre
Center fielder: Leonys Martin
Right fielder: Nomar Mazara
Designated hitter: Ronald Guzman
Backup catcher: Kellin Deglan
Utility IFer: Leury Garcia
Corner IFer: Christian Villanueva
Fourth outfielder: Jordan Akins

After signing with Texas late in 2009 for a reported bonus of $425,000, the Santo Domingo product was assigned to the Dominican Summer League in '10 and was brilliant. In 14 starts, he gave up more than one earned run only once, fanned 68 and had only eight walks in 70 innings. Perez finished the DSL season with a flourish, giving up one run in his final 45 innings of work (20 hits, four walks, 42 strikeouts), including a scoreless six-inning playoff effort in which he scattered two hits.

Overall, DSL opponents hit just .201/.234/.245 that summer against Perez, who posted a 1.41 ERA, never allowed a home run and coaxed more than twice as many ground-ball outs as fly-ball outs. Featuring a low-90s mph fastball and advanced feel for his curve, the then-17-year-old went into fall instructional league with as much buzz as any right-hander in the system. He came out of it with even more, as his fastball was up to 94-95 and touching 97.

This spring, Texas made the aggressive decision to assign the 18-year-old, who was ranked by MLB.com as the eighth-best prospect in the Rangers' system, to short-season Class A Spokane of the Northwest League, a circuit heavily populated by college Draftees. The organization decided the NWL would be a more suitable challenge than the rookie-level Arizona League after Perez, who registered 98 mph on the gun in camp, struck out 22 hitters and walked one in 13 extended spring innings, allowing three runs on 10 hits.

Perez was not only the youngest pitcher in the Northwest League, but also the Indians' Opening Day starter. He began the opener with a staggering eight strikeouts -- all swinging -- in his first three innings, flashing 97 mph velocity and a wipeout curve.

But he lost his release point and failed to register an out in the fourth inning that night, and as it would turn out, that frame and not the dominant first three would be the most indicative of his 2011 season. Perez posted an 8.31 ERA in nine winless starts, the final one of which was over after facing just four Eugene hitters. The 6-foot-5 right-hander drilled the first batter of the game and walked the next three. He was removed from the game and the Spokane rotation.

Perez made four relief appearances over the following four weeks, giving up five runs in 4 1/3 innings. He would finish the season with an 8.60 ERA and an unsightly 29 walks (plus eight hit batsmen and seven wild pitches) in 30 1/3 innings of work.

Rangers assistant general manager Thad Levine was a member of Colorado's baseball operations department in 2002 when the lanky Jimenez broke into the Minor Leagues by posting a 6.53 ERA for rookie-level Casper, despite packing mid-90s heat and a swing-and-miss curve.

"There were always a lot of moving parts with Ubaldo," Levine recalls. "It took him a while to mature into his own body."

When you read about "projectable" young power pitchers, it's easy to get excited about the thought that velocity and durability will increase with added size and strength, better conditioning and physical maturity. It's also easy to forget that kids who are still growing have to fight harder to repeat their deliveries. Sustaining mechanics can be an issue for any pitcher at any level. For a teenager whose body is changing, the challenge can be significantly greater.

Perez fought his mechanics all summer in 2011, regularly missing to the right side of the plate and falling into hitters' counts. But his upside is no less tantalizing than it was when he was dazzling the organization last summer in the Dominican Republic, and again in the fall and spring in Surprise, Ariz. Even with the severe command issues, he struck out 43 hitters in those 30 1/3 NWL innings and allowed only 25 hits (.223 average) -- just two of which left the park.

"We know that David possesses a big league arm and can spin a Major League-quality curveball," says Don Welke, the Rangers' senior special assistant to the GM. "He has the size and the assortment [of pitches]. He just needs time and experience."

With time and experience, Santana went from a pitcher who posted a 7.93 ERA in his first stateside Minor League season to a two-time American League Cy Young Award winner and owner for a time of the biggest contract for a pitcher in the history of baseball. Jimenez went from that 6.53 ERA with clumsy mechanics to becoming the National League's 2010 All-Star Game starter and the top starting pitcher moved at the Trade Deadline this year.

Each veteran had his growing pains right out of the gate, resulting in brutal numbers in spite of special stuff. Perez is the same age that Santana and Jimenez were when they were knocked around in their first seasons in the United States, and in fact was asked to pitch at a higher classification.

Perez's nine starts and four relief appearances could have gone much better this summer, but those 30 1/3 innings -- and the history of other pitchers who have overcome similar rocky starts -- shouldn't discourage anyone from believing that the 18-year-old could pitch at or near the top of a very good big league rotation when he grows into his considerable potential.