Irish hopes of what would have been a historic first series win on South African soil are already over but Easterby still anticipates a reaction from the Six Nations winners on Saturday.
“When you put in a performance that doesn’t match the levels the lads have put in across the last couple of seasons, then there is clearly disappointment,” he added.
“There is no better group to take responsibility for that, to get a second opportunity this weekend.”
Ireland struggled during the first half last weekend, giving up a try after only three minutes when the ball was quickly worked out wide to Kurt-Lee Arendse.
“They put the ball into space, which we anticipated, but we didn’t deal with that as well as we should have done,” Easterby said.
“Sometimes a team will find a way to get into space, we didn’t shut that down in the way that we would normally do.
“There are plenty of fixes for that but, essentially, we have to be better on both sides of the ball, especially in the first half.
“As the game went on we grew massively into the game and we finished strongly. We will take a lot of confidence from that.”
Ireland will name their team on Thursday afternoon with Rassie Erasmus having already confirmed he will field an unchanged squad for the game.
“That’s obviously a vote of confidence after their victory and it’s not unusual I guess,” said Easterby.
“It gives those guys a chance to back up with another performance.
“We expected a similar type of team and they’ve gone with the same 23, which probably makes it a little easier previewing them because we know a lot of their individuals and we’re aware of a lot of strengths in their team.”