Complex sentence: Martin became an unrestricted free agent in the summer of 2011; however, due to the 2011 NBA lockout, he opted to sign a one-year contract with the Xinjiang Flying Tigers of the Chinese Basketball Association.
Split into simpler sentences: Martin became an unrestricted free agent in the summer of 2011. However, due to the 2011 NBA lockout, he opted to sign a one-year contract with the Xinjiang Flying Tigers of the Chinese Basketball Association.