Cape Town - Ireland coach Joe Schmidt said on Saturday that the joy of a first Test triumph in South Africa was diluted by the "harsh" red carding of CJ Stander.
WATCH: CJ Stander knocks out Pat Lambie
The South Africa-born flank was sent off on 23 minutes in Cape Town after an aerial collision with Springboks flyhalf Patrick Lambie.
Concussed Lambie has been ruled out of the second Test in Johannesburg next weekend while Stander faces a disciplinary hearing in Cape Town on Sunday.
Despite being reduced to 13 men at one stage when centre Robbie Henshaw was yellow carded, Ireland shocked South Africa 26-20 at Newlands.
Schmidt believed French referee Mathieu Raynal got it wrong when he showed a red card to Stander.
"I thought the red card was very, very harsh," the New Zealand-born coach told reporters.
"CJ had both hands extended - once you are in the air you cannot change your trajectory.
"I know CJ and Patrick are friends. CJ was upset that Patrick was hurt as much as he was upset that he had to leave the field.
"Sometimes, I think when there is an injury like that, the consequence is that a card comes out."
After seven straight Test losses in South Africa, Schmidt admitted it was difficult to describe his feelings at breaking the duck before a stunned 46 000 crowd.
"It is pretty hard to put into words really," he said.
"I thought it was an incredible collective effort. The players can be incredibly proud of the effort they produced."
Schmidt refused to get carried away by the shock victory after the South African media wrote off an Irish team lacked injured stars like flyhalf Johnny Sexton.
One columnist said the England Saxons, the second-strong national squad who are also touring the republic, were stronger than Ireland.
"The Springboks probably let us off the hook a couple of times," conceded Schmidt.
"For all the effort we put into the game, there was a little bit of inaccuracy from the Springboks
"There were a couple of dropped balls when they really has us starting to go backwards defensively.
"But they still put us under real pressure. I thought Siya Kolisi really knocked us back a couple of times.
"Pieter-Steph du Toit brought a fair bit off the bench. Apart from that intercept try, his athleticism was very visible.
"I do think it looked like a first performance together for them. The fear I have is I have no doubt that they will improve in Johannesburg.
"We are incredibly excited by the little bit of history we created, the small step we took today.
"However, there are still two incredible large steps to take - one of them at altitude - and that will be very tough," said Schmidt.