Story highlights Sebastien de la Cruz, 11, sang the national anthem at NBA finals on Tuesday

Racists comments spread via Twitter after the Mexican-American boy's performance

Sebastien stands resilient: "I'm a proud American and live in a free country. It's not hurting me."

Father says he isn't "taken the comments personally, can't satisfy everyone"

An 11-year-old boy's rendition of the national anthem at Game 3 of the NBA finals brought the usual appreciative applause Tuesday, but outside AT&T Center in San Antonio, his performance brought a darker reaction from some posters on social media -- and eventually an online backlash against their racist comments.

Here's a sampling of some of the unkind tweets that went flying around the Internet about Sebastien de la Cruz

-- "Why they got a Mexican kid singing the national anthem -___-" from Daniel Gilmore

-- "How you singing the national anthem looking like an illegal immigrant" from Andre Lacey, proud father and firefighter from Augusta, Georgia.

-- "Why is a foreigner singing the national anthem. I realize that's San Antonio but that still ain't Mexico" from Lewie Groh.

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-- "Who let this illegal alien sing our national anthem?" from Matt Cyrus.

And the list went on and on.

As for Sebastien, he said the racist comments have not fazed him.

"For those that said something bad about me, I understand it's your opinion," said Sebastien to CNN. "I'm a proud American and live in a free country. It's not hurting me. It's just your opinion."

Sebastien has been singing since he was 5 but gained fame in 2012 after being on NBC's "America's Got Talent" for singing his mariachi ballads with hopes of winning to help his younger brother get surgery for his hearing problem.

Juan de la Cruz, Sebastien's father, hasn't taken the negative comments personally at all.

"When he was on 'America's Got Talent,' he faced racism there, too. You can't satisfy everyone," said de la Cruz to CNN.

"I think people reacted the way they did because Sebastien was wearing his mariachi outfit," said de la Cruz, "But, it doesn't make sense to listen to those people when most of the feedback we have gotten is positive. San Antonio supports Sebastien."

A collection of the negative tweets was posted on Public Shaming , a Tumblr blog dedicated to outing and shaming racists' social media posts. Other media outlets used that post as the foundation for the story, and the story took off from there.

The blog highlighted 28 tweets from NBA fans who came off as offended and ashamed that the Spurs would allow the boy, who happened to have been born and raised in San Antonio, to sing the nation's anthem.

However, Public Shaming must have suspected what would happen once the racist tweets were posted because most of the Twitter handles have been deactivated or the tweet has been removed. The blog posted screen shots of the tweets so it could continue to display the public microbloggers' rants.

After the harsh reaction spread across the Internet, tweets supporting and defending Sebastien and vociferously denouncing his critics started to take over:

-- "That little 10 year old mariachi National Anthem singer has more talent and grace than the combined racist pig idiots on Twitter," from Mexican-American cartoonist Lalo Alcaraz

-- "Racist scumbag says Chicano kid singing nat'l anthem just "snuck into the country." This idiot's apparently of color too. @A2daO," from Laura Gonzalez, a Chicana Santa Rosa City Schools board member and middle school teacher.

-- "Why are ppl so upset over a Hispanic singing the national anthem. He's probably got more roots in here than most 'Americans'," said Amanda Aguirre on Twitter

-- And, from the American Latino Museum , "We're proud of the 11-year old San Anto-native Sebastien de la Cruz for his amazing performance last night!"

San Antonio is a multicultural city with more than 55% of the population being Hispanic and 90% of those people identifying themselves as Mexican according to the Pew Hispanic Center

For some Mexican-Americans, the incident was just the latest sign of a persistent problem they face: being treated as outsiders in their own country.

"To see people acting this way doesn't make sense anymore. It's a demographic fact that the country is changing and Latinos are going to be behind that economic push that moves everyone forward," said Chon Noriega , director of the UCLA Chicano Studies Research Center, to CNN. "Cities like San Antonio are defining a trend of a nation."

That the word "Mexican" is being used as a derogatory term is part of the problem, said Noriega, "It's become the N-word of Mexican descent. Yet it's also the name of a group of people in a neighboring country."

It will take a lot more than some racist tweets to bring Sebastien down.

The "boy with the golden voice" tweeted earlier today : "Please do not pay attention to the negative people. I am an American living the American Dream. This is part of the American life."

Sebastien said today was like any other day, but he's always grateful to wake up to yet another day able to sing. He said he owes his positive outlook to his parents, family and everyone in San Antonio.