"It's phenomenal how these students operate, our rugby sides, our cricket sides, our tennis sides and our hockey sides."
During his time in the role, multiple Collegiate students have gone on to become professional athletes, including long-distance runner Geordie Beamish and All Black Stephen Perofeta.
Touzel said many students had received international university scholarships off the back of their sports, especially in athletics and rowing.
"A lot of these guys might not become professional-level athletes, but they're operating at a level where they're nationally recognised which allows them to go to the States and further their education because the sport has given them a pathway," he said.
The success of the school made him proud as it proved the structure he had headed, and the work the school had put in as a collective, had worked.
"It must have because we don't have the numbers to just be a numbers game, it has to be the coaching of our specialist coaches. So I think we can be very proud as a school of what we've achieved over the last decade or so."
The changes in sport structure at the school had exceeded what even he had expected.
"I'd thought it would help but if you'd asked me eight years ago if we'd have all these rugby players, I'd have said no way."
The success of the school was not down to him, he said, but rather the staff and specialist coaches of the school allowing them to compete with schools with much higher team numbers.
"It was my vision, but it was fully supported by the school and the boards and so on."
He said the absolute support the school gave him, especially over the past four years under headmaster Wayne Brown, led to the school's success.
Brown said during the past eight years Touzel had brought diligence, insight and a spirit of excellence to the role and he wanted to highlight the unseen areas of Touzel's service now he was stepping away.
"Barry is often the first non-residential member on site each day, checking wickets, setting fields and making sure all is in order.
"He has stepped in on so many occasions throughout the school to provide support and guidance to staff, students and members of the community and, as an ex-professional sportsman, his mentorship to our aspiring athletes has been invaluable," Brown said.
After his time in the role, and with the school's teams operating at a high level for the past three years, Touzel felt it was time to step aside and let a fresh set of eyes take over and drive the school's sporting efforts further into the future.
"That's probably going to be a phase of maybe two, three, four, five years, and I've run my race."
However, Touzel will stay with Collegiate, taking up the position of sports master which he said would greatly reduce his responsibilities.
Instead, he will focus his efforts on sports administration and aspects like the appointing of coaches, and backing up the new director of sport.
"I'll still be involved with the sport, but at a real grassroots ... day-to-day running position."