The side won 30-27 after trailing 19-10 at the break and Mauger was happy with the win.
''I was very proud of the resilience shown by the guys.
''Our leaders were outstanding and we were able to maintain our composure at the back end of the game,'' Mauger said.
He praised the play of new first five-eighth Josh Ioane.
''I thought he was outstanding but then I knew he would be outstanding and that is why I picked him.
''We had a good nucleus of our leadership ground out there at the end.''
He said the plan for the first game was to put the faith in the young players and they had repaid him with some fine efforts.
The players had worked hard in pre-season and showed how well they wanted to perform.
''The way they have trained in the pre-season and then played in the two pre-season games we thought they were ready to perform.
''There were some questions and speculation about those guys but we had faith in those guys to do the job."
Mauger said the side made a few too many mistakes in the middle of the game and the Chiefs came back well which they were always going to do.
He had not had a hard look at the red card dismissal of replacement back Sio Tomkinson.
''We'll have to have a good look at it ... we've got a pretty disappointed Sio Tomkinson back in the changing shed. He feels like he let the team down but we will support him and get round him.''
''To win away from home and all the challenges that we had at the end of the game then the win was massive.''
Chiefs coach Colin Cooper was disappointed to lose but paid tribute to the Highlanders leadership group which steered the win.