Complex sentence: The Mavs signed him to a second 10-day contract on January 18,2013, and signed him for the remainder of the season on January 28, after his second 10-day contract was up.
Split into simpler sentences: The Mavs signed him to a second 10-day contract on January 18,2013. The Mavericks signed him for the remainder of the season on January 28, after his second 10-day contract was up.