"What an effort from a 20-year-old - to play 70-odd minutes is huge," Robertson said of Allen, who is in his first year at this level. "He's got a great future. There was sort of a little bit of Wyatt Crockett about it, to come on and just do the job. For a young fella, [I'm] really proud.
"[Assistant coach] Jason Ryan has done a lot of work with [our] props - all our props, to get them ready at any time. It was a bit see-saw there, but in the end, we did enough, and created enough off our scrums to still perform."
Otherwise it was all just about good news for the Crusaders, who in scoring nine tries to four showed why they will be hot favourites to make it Super Rugby title No 3 under Robertson. They are out by themselves at the top of the table.
Skipper Ryan Crotty was as accurate as always and returned to the pitch following a head injury assessment. And with debutant Sevu Reece and Will Jordan, Jack Goodhue, Braydon Ennor and replacement fullback David Havili running amok in the backline, the Crusaders had far too much firepower for a struggling Chiefs team yet to win this year.
"We were a bit more ruthless," said Crotty of the Crusaders' finishing.
In their previous home game, the Crusaders allowed the Hurricanes to score two late tries to deny them a winning bonus point, but while the Chiefs scored a late brace, Crotty's men were out of reach.
"We put it right out of touch," he said. "Still disappointing to let them get a couple of dots at the end, but that's the bar we set for ourselves."