Carrera signed with the New York Mets as a non-drafted free agent on April 4, 2005. He spent the 2005 season in the Venezuelan Summer League and batted .227 with eight RBIs and 19 runs scored in 45 games.

In 2006 he hit .301 with one home run, 19 RBIs, 41 runs scored and 22 stolen bases in 57 games in the Venezuelan Summer League. He went 4-for-5 with two runs scored, an RBI and a stolen base on June 2. Carrera stole three bases on June 13.

He started and spent most of the 2007 season with the Rookie-League Gulf Coast League Mets of the Gulf Coast League but also played with the Short-Season Brooklyn Cyclones. He hit .329 between the two clubs with 82 hits, 10 doubles, three triples, one home runs, 32 RBIs and 22 stolen bases.

In 2008 he spent the season with the Class-A St. Lucie Mets where he served as the primary leadoff hitter and ranked fourth in the Florida State League with 28 stolen bases.

The Mets traded Carrera along with Endy Chávez, Aaron Heilman, Mike Carp, and Jason Vargas to the Seattle Mariners in a 12-player deal on December 10, 2008.

Carrera had a break-out 2009 season batting .337 with two home runs, 38 RBIs and 27 steals batting lead-off for the Double-A West Tenn Diamond Jaxx of the Midwest League. He was named to the Southern League Mid-Season All-Star Team on June 29. He was placed on the disabled list on July 9 with a right thumb injury. He was reinstated on August 1. Carrera and teammate Greg Halman were selected to the 2009 Southern League Postseason All-Star Team as voted upon by the league's field managers, radio broadcasters and print media. Carrera was also a mid-season All-Star selection as well is leading the league in batting average.

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Wikipedia