The 23-year-old winger, who missed the Tri-Nations Series with calf and knee problems, has benefited from All Blacks coach Graham Henry's decision to name a completely different XV from that which beat Wales.
The Waikato ace said: "I was a little bit rusty during NPC but it's good to be back and learning off the guys. There's a lot of competition going on between the guys and it really keeps us honest. I've been working really hard.
"With Rico (Gear), Joe (Rokocoko), Dougie (Howlett) around - you just have to work your butt off."
Captain Tana Umaga has been left out of the squad but hooker Keven Mealamu has been included in the side.
Prop John Afoa and lock Chris Eaton will make their Test debuts at Lansdowne Road, as the All Blacks continue their quest for a Grand Slam tour.
Aaron Mauger is also in the line-up and looking forward to locking the horns with the side against whom he made his Test debut in 2001
"I've had some pretty memorable moments and it sits up there as one of the best moments in my rugby life," Mauger recalled, having scored a try that day in a 40-29 win.
Mauger believes New Zealand will be just as strong against Ireland despite all the changes and told www.nzrugby.com: "If you look at what potentially can go out there it's not too different in terms of strength to the first backline.
"After the first team got named we all started running together, we pretty much know it all now.
"We're excited but we're aware we can't be complacent. In the past we've had good performances and then let ourselves down the next week and just scraped through."
New Zealand team to play Ireland at Lansdowne Road on Saturday, November 12:
L McDonald (Canterbury); D Howlett (Auckland), M Nonu (Wellington), A Mauger (Canterbury), S Sivivatu (Waikato); N Evans (Otago), P Weepu (Wellington), T Woodcock (North Harbour), K Mealamu (Auckland), J Afoa (Auckland), C Eaton (Taranaki), A Williams (Auckland), S Lauaki (Waikato), R McCaw (Canterbury), M Tuiali'i (Canterbury).
Replacements: A Hore (Taranaki), S Taumoepeau (Auckland), C Hayman (Otago), C Jack (Canterbury), R So'oialo (Wellington), J Cowan (Southland), M Muliaina (Auckland).