Tighthead prop Charlie Faumuina and loosehead Tony Woodcock are coming on to their games, which can only be good for Steve Hansen's blood pressure, among others.
"I think it's going really well. It's a massive change from where it was a month ago, where it was something that wasn't reliable to set a platform for our backs. Now we can have a go at other teams off that, so the confidence in the boys is up," said Faumuina, whose 2013 Super Rugby season was wrecked by calf issues, much like Mealamu in 2014.
Tuipulotu brings much-needed scrum beef behind Faumuina at tighthead lock.
Some technical tweaks on the engagement with scrum coach Nick White have also proven useful.
This Friday night Faumuina will lock horns with wily, 66-test Waratahs veteran loosehead Benn Robinson.
"It's always been an interesting battle over the last few years. If he gets his way, he can get into a nice, strong position and give you trouble all night, but if you can control his angles, we're sure we can take care of him."
The Blues, of course, have got other issues to tweak or overhaul, not the least of which is their breakdown work, where they were well beaten by the hungry Hurricanes, and implementation of their game plan.
"It's a defining game of the season for us," said Faumuina. "We really need this game and the Reds [on May 2] to get back on track."
Chris Noakes, who was concussed against the Hurricanes, did not come through tests yesterday with flying colours. Kirwan could promote new squad member Ihaia West to the bench with Simon Hickey resuming his starting role. Kirwan did rule out playing the returning Piri Weepu at first five, but the halfback is medically fit for selection at either No 9 or 21.
The engine room
• Tony Woodcock: All Black caps 107, Super Rugby 132
• Keven Mealamu: 110, 154
• Charlie Faumuina: 17, 53
• Tom Donnelly: 15, 90
• Patrick Tuipulotu: 5 (in Super Rugby).