The 23-year-old made history when she scored Banyana Banyana's maiden Women's World Cup goal in the 25th minute to help them to a first-half lead.
However, Kgatlana's effort was not enough to see the 10-player African side avoid a losing debut as Spain benefited from two penalty decisions to come from behind to win 3-1.
Although pleased to make scoring history for South Africa in the Women's World Cup, the reigning African Women's Footballer of the Year is saddened by the loss.
“It’s an amazing feeling for me to get my first goal in the Women's World Cup and one for the country because it’s our first time coming here," Kgatlana told media.
"However, I’m a little bit disappointed that we didn’t win the match based on two decisions from the VAR. There’s nothing we can do about it, it’s part of football and we have to adapt to it.
“It was amazing (to hear the fans cheer), but I’m here to play for the country and represent the team, and also to represent the people in the stadium.
"Even when they cheer me I have to focus and do my job - everything else will come after.”
The opening defeat leaves South Africa at the bottom of Group B standing with no point and they will aim to get their campaign back on track against China on Thursday in Paris.