The 35-year-old Rosas, who began his nine-year tenure with the Rockets as an intern and rose through the ranks, will report to Dallas president of basketball operations Donnie Nelson.
"I went to Donnie and said, 'We need to get smarter as an organization and we need to really expand what we're doing,'" Cuban said Monday on ESPN Dallas 103.3 FM's Galloway and Company. "We try to take pride in being one of the most technologically advanced teams in all of sports, not just the NBA, and to keep on pushing the envelope in directions that I wanted to go, we needed to not just add brainpower but organizational management and process power.
"I asked Donnie to go out there and find out who he thought would be the best person to do this, and he came back with Gersson's name."
Nelson had been Dallas' de facto general manager, a position the Mavs have not officially had since his father, Don, left the franchise in 2005.
Cuban cited the need for strong management skills as the reason for adding Rosas, who played a critical role in helping Houston general manager Daryl Morey reshape the Rockets' roster. The Mavs have expanded their analytics group and are researching several scientific and technological areas in an attempt to create advantages.
"My strength is in pushing the envelope," Cuban said. "Donnie's strength is in talent evaluation and pushing the international envelope. We really needed somebody with stronger organizational and management skills to pull all these pieces together. As we continue to add new pieces, we just needed that strength.
"When we found somebody with that process and management skill like Gersson and also somebody who has experience working with an analytics group, working with a D-League team, working in talent evaluation, that was just an added plus that made him the perfect candidate."
The Mavs' agreement to hire Rosas, a native of Bogota, Colombia, was reported earlier by Yahoo! Sports.