In making several changes to his backline for the Lions match - Simon Hickey, Jackson Willison and Tevita Li making way for Chris Noakes, Pita Akhi and Charles Piutau respectively, with Benji Marshall starting at fullback - Kirwan has shown a willingness to tinker.
Kirwan yesterday confirmed he was pleased with Hall's performance, along with the efforts of fellow substitute Hickey.
Piutau was again strong despite limited opportunities, with Halai also dangerous in the second half. Marshall showed up once the Blues got on top - his try was a solo effort in which he jinked and stepped past several defenders.
Nonu will come into the midfield equation, possibly for Akhi, with Kaino a possibility at No8 alongside flankers Steven Luatua and skipper Luke Braid.
Kirwan said he would receive the results of hooker Keven Mealamu's knee scans this week and the veteran was a possibility for selection.
The two bonus points were eagerly accepted by Kirwan but the Blues should have got more out of their South Africa trip. It was again a case of what might have been - the performance of his backs in the second half papering over a below-par effort from his forwards.
"It's a tough start as we were hoping to come home from South Africa with more points," Kirwan said. "The reality is we've got seven. I think we're ninth on the table, we're hanging in there and now we have two home games, the hard travel for us is over."
Lions 39 (Faf de Klerk, Coutnall Skosan, Coenie van Wyk tries; Marnitz Boshoff 3 cons, 4 pens, 2 dropped goals).
Blues 36 (Charles Piutau, Bryn Hall, Frank Halai, George Moala, Benji Marshall tries; Chris Noakes 2 cons, pen, Simon Hickey 2 cons).
Halftime: 17-0