"It was a reminder to the players about what it means to the opposition to play against the Lions. They came at us at 100 mph in the first 20 minutes and the boys had to soak up the pressure," said Gatland.
"The first twenty is what playing for the Lions is about. For us to soak up the pressure, guts it out and come away with a win makes me very proud of the performance.
"It was exactly what we wanted. We've known that with the amount of travel we've done, added to the fact we've trained a little longer and harder than usual, and had a new formation out there again, we were going to be a little bit flat in the legs.
"The boys stuck at it when under some pressure and showed good character. The weather conditions in the second-half didn't help - it was a territory game but we showed great courage and guts
"We missed out on a couple of opportunities, in terms of a couple of tries which were very close. But they kept digging deep and did what was required and I'm pretty pleased with that."
It was also a night on which Owen Farrell proved his worth as he kicked 17 points with a perfect record of six out of six goalkicks. It was a contribution that didn't go unnoticed by the coach.
"I thought he was great. His composure and goalkicking were great and he ran well. The thing you admire about Owen is that given his age if he has a set back he has the competitive edge to go away and think about his game, works hard and improves. If he's not on form for one game you rarely see him backing that up in another," added Gatland.
"These first three games have been very much about ourselves - we haven't looked at the opposition much, Even though the Reds had a number of players away with the Australian side, ours was a new combination playing against a side with 16 rounds of Super Rugby under their belts plus a pre-season.
"Their players were very familiar and comfortable with each other and from that point of view we are very happy with that result. They tried to run us off the park and I hope the Wallabies try to do the same.
"We think we are in pretty good shape physically. I know the boys were blowing a bit, but from a coaching point of view when the Test series comes around we will be in good shape.
"With the travel and training we have done we have over trained and taken away the legs from them. I thought we were pretty good fitness wise and it all bodes well for what is going to be a pretty exciting series by the look of it."