The teams were level at halftime at 6-6 and both sides scored two second-half tries, but in the end an extra penalty goal by Ireland saw them claim the three-point victory at the Aviva Stadium.
Reflecting on the match, Mostert said: “The guys that started did a good job to get us 22m entries, but we couldn’t finish our chances. The bomb squad came on and picked up the pace as expected, but in the end, we couldn’t get the result.
“We are very disappointed with the result, but all we can do now is focus on correcting the mistakes we made and ensure that we play better next week.”
Hendrikse echoed his team-mate’s sentiments: “We need to improve and be more clinical in our execution. We created a few chances in the game, but we didn’t use them, so that is one of the areas we must improve on.”
When quizzed about the influence this result could have on the team with an eye on next year’s Rugby World Cup in France, where they will line up in the pool stages, Mostert said the Rugby World Cup is still a long way away.
"But what we will take out of this game is that it was good experience for the players who have never faced Ireland and playing in front of a capacity crowd away from home. That will be invaluable for us before and during the World Cup.”
The Springboks departed for Marseille on Sunday and will return to the training field on Monday to begin their preparations for Saturday's outing against France.