The 38-year-old has signed with Waikato for the Mitre 10 Cup season, extending his professional rugby career to nearly the 20-year mark.
After playing age-grade rugby for New Zealand, Thomson signed a professional contract straight out of school and went on to play 30 times for the All Blacks, more than 100 Super Rugby games across four franchises in New Zealand and Australia and for clubs in Japan and America.
