''In that time he's certainly grown. When he started with us he was sparring 60-kilo people. He's got to 105 kilos in a very short time and now he's sparring with fully grown men - and giving them a run for their money,'' he says.
Te Kehu first began going to Te Puke Box, also owned by Chris, to lose weight.
''My dad pushed my brothers into doing boxing before me and I just kind of did it in Te Puke and took a liking to the sport, and then the Te Puke manager told me to come to here [to Tauranga],'' he says.
Te Kehu attends Te Wharekura o Mauao in Bethlehem and stays in Tauranga on Tuesdays and Thursdays to train.
He was 13 when he first decided he'd like to get into the ring and it was another year before his first fight. Most of his six wins have been on points and he enjoys both the bouts and the preparation.
''The training helps so much towards my fights. And I do a lot of sparring and stuff that helps with a lot of fitness with both my sports because I love playing rugby as well.
''I'm still developing my technique, I'm not at my peak yet, so I'm working on that and trying to attend every training and take every chance I can to try and upgrade my skills.''
The national tournament last month was the delayed 2020 championship and there will be a 2021 tournament later in the year. Winning at that and this year's Golden Gloves are goals for the year.
Chris says Te Kehu is ''pretty driven and pretty tough''.
''Physically he's got it and mentally he's quite strong. Boxing's not for the faint-hearted, so in that respect he's doing well.
''Technique-wise he's coming along. Now it's all about experience and he's still got a long way to go. That's quite exciting because it means he's got a lot of improvement to be had. From where he is now to where he will be having had 25 fights will be a big dramatic shift.''
Te Kehu could be fighting again next month.
''The boxing scene has fired up again and there are tournaments running right through and there are some bigger boys around for him to fight now.
''The next thing for him is to really enhance his ability and skills and get more experience under his belt - that's how he'll get better in the long run.''