Neifi Neftali Pérez (/ˈneɪfi, ˈnɛfi/; Spanish: [ˈnejfi]; born June 2, 1973) is a Dominican former Major League baseball player.

During his career, he played with the Colorado Rockies, Kansas City Royals, San Francisco Giants, Chicago Cubs, and Detroit Tigers.

Frequently praised for his defensive skills, Pérez reached the major leagues in 1996 and became the Rockies' shortstop for good in 1997.

As a Tiger, he turned a double play which saved Justin Verlander's no-hitter, but he also had a series of positive tests for amphetamines which effectively ended his career.

Assigned to the single-A Bend Rockies for the 1993 season, Pérez posted a .260 batting average and stole 19 bases.

[2] Pérez exhibited strong defensive skills, executing the first unassisted triple play in the history of the California League in a game against the Bakersfield Blaze.

[3] Pérez batted just .239 on the year but made the California League All-Star game and was considered to be one of the Rockies' top prospects on the basis of his defense.

Rockies player development chief Dick Balderson expressed confidence that Pérez's hitting would improve: "He's got all the skills...He's just in a rush right now, like most young guys.

"[4] Pérez moved up to the double-AA New Haven Ravens where he batted .253 and improved his fielding percentage to .967 and was considered the Rockies' top prospect at shortstop.

[5] The Rockies promoted Pérez to triple-A Colorado Springs Sky Sox at the end of the 1995 season with the intention of bringing him up to the major leagues the next year.

Although invited to 1997 spring training Pérez did not make the 25-man roster and once again returned to the Sky Sox for the first half of the season, where he batted .363 with a .975 fielding percentage.

Pérez also may have sealed his fate by refusing to enter a late-season game at the request of manager Tony Peña.

Although signed as a starter at second base, he quickly became backup to Ray Durham, while he lost out at shortstop to Deivi Cruz.

[20] Manager Dusty Baker made Pérez the everyday shortstop in 2005 to replace Garciaparra, mainly on the strength of his defensive skills.

[25] Pérez arrived in Detroit during the pennant chase which ended with their loss in the 2006 World Series to the St. Louis Cardinals.

One bright spot came on June 12, 2007, when he saved Justin Verlander's no-hitter against the Milwaukee Brewers by turning a possible base hit into an inning-ending double play.

[30] In February 2008 there was talk of the Colorado Rockies signing Pérez to a minor league contract worth $750,000, which manager Clint Hurdle characterized as a "lifeline."

He played in the Dominican Professional Baseball League for Leones del Escogido with personal success, batting over .300.

[36][37] Chicago sportswriter Bruce Miles called Pérez "one of the worst offensive players in baseball history.