Lewis has pitched very well in Japan, posting a 2.96 ERA in 2009.
"We've developed our Pacific Rim operation the last few years, and our guys have built a solid foundation both with relationships and from a scouting perspective," Rangers general manager Jon Daniels said. "I expect we'll be selectively involved with the right players coming over. We're aware of Colby's situation, and obviously know him from when he was in the organization."
Lewis, a former Rangers draft pick, last pitched in the MLB in 2007. He was 11-9 with a 2.96 ERA for Hiroshima in 2009 after going 15-8 with a 2.68 ERA with 183 strikeouts in 178 innings the year before.
The Rangers are interested in bringing in another arm, but have maintained the mentality of having as much pitching depth as possible, and believe Lewis may have crossed a threshold where now he can compete in a major league rotation.