The Rockies assigned him to the Colorado Springs Sky Sox of the Class AAAPacific Coast League (PCL). and promoted him to the majors in late July. He made his debut on July 31 and went 1-3. In each of the next three seasons, Quintanilla began the season with Triple-A Colorado Springs and was promoted to the majors at least once each season. In limited at-bats, he had his highest batting average in 2008 at .238.
The Office of the Commissioner of Baseball announced August 11, 2010, that Quintanilla had received a 50-game suspension after testing positive for Methylhexaneamine, a performance-enhancing substance, in violation of the Minor League Drug Prevention and Treatment Program.[2]
Texas Rangers
Quintanilla signed with the Texas Rangers after the season and in July 2011, he had his contract purchased by Texas after hitting .298 in 51 games with Round Rock Express of the PCL. On August 1, he was outrighted to back to Round Rock and elected free agency. Overall with the Rangers, he hit .045 in 11 games, with two RBI.
On July 20, 2012, Quintanilla was traded to the Baltimore Orioles for financial considerations.[5]
He played 2nd base for the Orioles. He had 4 home runs and 15 RBIs.
Second stint with Mets
On January 5, 2013, Quintanilla signed a minor league deal with the New York Mets which included an invitation to Spring Training. His contract was purchased and he was subsequently called up on May 30 when shortstopRuben Tejada was placed on the 15-day disabled list. The Mets moved closerFrank Francisco from the 15-day to the 60-day disabled list to make room on the 40 man roster.[6] He became a free agent on December 2, 2013, after being non-tendered. He re-signed to a minor league deal in January 2014. He was designated for assignment on May 8, 2014. Quintanilla elected free agency in October 2014.[7]
Second stint with Colorado Rockies
On January 30, 2015, Quintanilla signed a minor league contract with the Colorado Rockies. He was released on June 15, 2015 after appearing in only two games for the Modesto Nuts.[8]
Toros de Tijuana
In 2016, Quintanilla made his debut in the Mexican League with the Toros de Tijuana. He became a free agent after the 2017 season.