|Age: 36 (born September 12, 1975)|
|Position: Second Base|
|Bats: Switch Throws: Right|
|Acquired: Trade with Twins on July 30, 2007|
During the ’07 season, Castillo came to the Mets in a trade with the Minnesota Twins. He collected 59 hits in 50 games over the rest of the year. At Chicago on August 5, Luis had three singles, a double, two stolen bases and a pair of runs scored in the Mets’ 8-3 win over the Cubs. He hit a game-tying two-run single in an eventual 4-3 Mets victory over the Braves on August 8 at Shea Stadium. Castillo had a single, a homer, two runs scored and two RBIs in a 7-4 Mets triumph at Washington on August 18. He drove in the winning run with a ninth-inning single for a 7-6 Mets victory over the Padres on August 21 at Shea. Luis singled, doubled twice and scored two runs in the Mets’ 10-4 win at Cincinnati on September 3. He also had a single, two doubles, two runs scored and two RBIs in a 13-0 Mets triumph over the Marlins on September 29 at Shea.
An injured left hip limited Castillo to 87 games in 2008. He accumulated 91 total bases during the season. On April 16, Luis singled three times in a 5-2 Mets win over the Nationals at Shea. He had two singles, a double and a run scored in a 6-3 Mets victory over the Braves at Shea on April 27. Castillo hit a two-run homer in the Mets’ 7-6 triumph over the Marlins in 12 innings on May 28 at Shea. One day later, he had two singles, a double and two runs scored in an 8-4 Mets win over the Fish. Luis had two singles, two stolen bases and five runs scored in the Mets’ 15-6 victory over the Yankees on June 27. He also had three singles and an RBI in a 3-1 Mets win over the Yanks on June 29 at Shea.
In 2009, Castillo led the Mets with 131 singles. He had a .302 batting average and drove in 40 runs for the season. At Florida on April 11, Luis singled four times and scored three runs in the Mets’ 8-4 victory over the Marlins. He singled in the ninth inning to drive home the winning run for a 5-4 Mets triumph over the Brewers at Citi Field on April 17. Castillo had two singles, two stolen bases and a sacrifice fly in the Mets’ 8-4 win over the Pirates on May 10 at Citi Field. He singled and scored twice each in a 7-4 Mets triumph over the Nationals at Citi Field on May 27. Luis singled, doubled twice and scored all the Mets’ runs in a 6-3 defeat to the Phillies in 10 innings at Citi Field on June 11. The very next night versus the Yankees in the Bronx, he dropped a routine pop up from Alex Rodriguez in the bottom of the ninth with two outs, leading to two unearned runs that gave the Yankees a 9-8 win. He had a pair of singles, a run-scoring double and two runs scored in a 6-4 Mets victory over the Cardinals on June 22 at Citi Field. Castillo singled and scored three times each and had a sacrifice fly in a 9-7 Mets win over the Reds at Citi Field on July 12. He had a run-scoring single that put the Mets ahead to stay in a 6-4 triumph at Arizona on August 12. Luis slugged a two-run homer in the Mets' 3-2 win over the Giants at Citi Field on August 16. He also had three singles and two runs scored in a 9-7 Mets loss to the Phillies on August 23 at Citi Field.
Castillo had 58 hits in 2010. He scored 28 runs during the season. Luis singled, doubled and scored two runs in a 5-0 Mets win over the Rockies at Colorado on April 15. He singled home a pair of runs in a 4-0 Mets triumph over the Dodgers in the first game of a doubleheader on April 27 at Citi Field. Castillo hit a two-run single that put the Mets ahead to stay in an eventual 10-4 victory over the Brewers at Milwaukee on May 30. He singled, doubled and scored a run in the Mets’ 3-2 win at Atlanta on August 3. At Citi Field on August 24, Luis singled in the ninth inning to drive in the winning run for a 6-5 Mets triumph over the Marlins. He also scored the winning run in the ninth inning in the Mets’ 4-3 victory over the Brewers on September 28 at Citi Field.