"We were obviously disappointed with the loss against the Highlanders and realise that we need to improve in several areas, including our discipline, but we feel that overall we are building well towards the Test matches.
"Every game is a big challenge, which is what we wanted, and this is an experienced Lions team with eight of the starting 15 involved in the last Test in Australia in 2013."
Gatland added: "Peter is a proven captain with Munster who never takes a backward step and we believe that those leadership qualities will serve us well on Saturday against a quality and determined Maori All Blacks team."
British & Irish Lions squad
1. Mako Vunipola - Saracens, England
2. Jamie George - Saracens, England
3. Tadhg Furlong - Leinster, Ireland
4. Maro Itoje - Saracens, England
5. George Kruis - Saracens, England
6. Peter O'Mahony (capt) - Munster, Ireland
7. Sean O'Brien - Leinster, Ireland
8. Taulupe Faletau - Bath Rugby, Wales
9. Conor Murray - Munster, Ireland,
10. Johnny Sexton - Leinster, Ireland,
11. George North - Northampton Saints, England
12. Ben Te'o - Worcester Warriors, England
13. Jonathan Davies - Scarlets, Wales
14. Anthony Watson - Bath Rugby, England
15. Leigh Halfpenny - Toulon, Wales
Replacements
16. Ken Owens - Scarlets, Wales
17. Jack McGrath - Leinster, Ireland
18. Kyle Sinckler - Harlequins, England
19. Iain Henderson - Ulster, Ireland
20. Sam Warburton - Cardiff Blues, Wales
21. Greig Laidlaw - Gloucester Rugby, Scotland
22. Dan Biggar - Ospreys, Wales
23. Elliot Daly - Wasps, England