Robertson will have a post-season break before preparing to take over the All Blacks once the 2023 Rugby World Cup is completed in France in October.
Part of that time will be spent reminiscing on a unique feat in the professional game in New Zealand.
Going into a final against the Chiefs, the outright winners of the minor premiership, the Crusaders had to dig deep into their player reserves after an injury-affected campaign. Yet, they were still able to come up with a win.
His captain and lock, Scott Barrett, said, "We were disciplined enough and kept plugging and plugging.
"We eventually got the reward and just had to stay patient. The leaders around me were immense in keeping the group pretty level."
Robertson paid tribute to lock Sam Whitelock, who overcame an Achilles tendon injury, and a medical recommendation that he shouldn't play, to complete his career with a seventh Super Rugby title.
"He deserves a special mention. He played 80 minutes and wasn't going to come off. We think he's an immortal and is a god-like figure with what he's done. The amount of games he's played, when he was captain year after year, he rises every day. For him to have this moment is pretty special.
"In his mind, he was always going to play, it was his Achilles that was going to say no. The dock said 'no', but it's the way he is with his mindset."
Whitelock said he was expecting some grief from the All Blacks' team management about playing, but that was countered by being able to sign off with so many others who had contributed to the franchise.
Barrett also praised his locking partner.
"He's a calming influence. You know you've got someone who is an immortal of our game. He's a winner, he's a competition. He lays everything out there, and I'm immensely proud to call him a mate. He's given so much to this jersey over 14 or so years."
Another player who has been significant in Robertson's tenure was first five-eighths Richie Mo'unga, who is also departing the franchise.
"Richie was sublime. He's a finals footballer, a genuine, world-class finals footballer. He's a winner who stays in the fight."
Robertson said he had been turning up to Christchurch's Rugby Park in playing and coaching roles for 23 years. He loved the game and said rugby had given him and his family so much.
"To finish on this note makes it even more special because it could have gone the other way. It feels awesome because nothing is given, everything is earned."
Robertson said the result came down to small margins.
"The Chiefs were unbelievable. Their defence was incredible.
"They've had a great season and Clayton has put a good squad together."
Had they won the final, they would have deserved it, he said.