The Crusaders went first to their strength - the set piece - and they had the Jaguares in trouble, despite, or perhaps because of, the 10 reinforcements inserted by coach Raul Perez. Hooker Agustin Creevy, their skipper, was good, but the backline was abysmal, the combination between halfback Gonzalo Bertranou and first-five Juan Martin Hernandez looking rusty in the extreme.
The Crusaders, back from their three-match trip to South Africa and Australia, showed no signs of tiredness, and quickly reverted to an offloading game which the visitors had no answer to.
Halfback Ellis, in some of the best form of his life, was over after five minutes from a Crotty bust and Dagg draw and pass, and Dagg turned recipient on the quarter mark, taking advantage of the yellow card for opposite Joaquin Tucolet.
Four minutes later, Richie Mo'unga was over after picking the pocket of centre Jeronimo De La Fuente. A penalty on the stroke of halftime pushed the score out to 22-3 and it was only a matter of whether the Crusaders could pick up a winning bonus point.
A try for No8 Fecundo Isa took the Crusaders out of the three-try advantage zone, but, despite Blackadder's men looking a bit scrappy as they searched for the extra point, it came when Read went over and Dagg scored his second, a brilliant effort in which he burst on to the ball, went through two defenders and around the fullback Tucolet.
All this following 30 minutes of rugby for his University club - it was no wonder, Dagg, who got a deserved rest after 64 minutes, was smiling afterwards.
Second-five Santiago Gonzalez Iglesias ran on to a well weighted kick to narrow the gap, but his team will leave New Zealand disappointed after their defeats to the Blues, Hurricanes and now the Crusaders.
It got scrappy for the Crusaders at times as they searched for the bonus point, but, having moved to second in the New Zealand conference and fourth overall, they are in a good position to push on for the playoffs.
Crusaders 32 (Andy Ellis, Israel Dagg 2, Richie Mo'unga, Kieran Read tries; Richie Mo'unga 2 cons, pen)
Jaguares 15 (Fecundo Isa, Santiago Gonzalez Iglesias tries; Juan Martin Hernandez pen, con)
Halftime: 22-3