But as he made the second week in Melbourne and his profile grew, so did the number of inquiring minds keen to learn more about the 26-year-old from Tennessee.
As people scrolled through the world No. 97's Twitter feed, a social media storm began to brew. Sandgren was linked to alt-right beliefs because of some of the people he follows on Twitter and several of his retweets.
So rather than answering questions about his tennis career, Sandgren found himself being asked if he supported the alt-right movement.
"No, I don't," he replied. "I don't. I find some of the content interesting. But no, I don't, not at all. As a firm Christian, I don't support things like that, no. I support Christ and following Him. That's what I support."
Sandgren has since deleted the overwhelming majority of his tweets, with 37 listed but only one shown as of Wednesday after he lost his quarterfinal in straight sets to South Korea's Hyung Cheon.
But it was too late -- The New York Times had reported
that on January 14 Sandgren retweeted a video posted on Twitter from Nicholas Fuentes, who the newspaper described as an alt-right commentator. Fuentes lists himself on Twitter as the host of America First.
As the newspaper also pointed out, Sandgren appeared to believe that "Pizzagate"
Then there were screengrabs showed him getting into a debate
with retired tennis star James Blake about the subject of police brutality. Blake -- whose father was African American -- was slammed to the ground in 2015 in New York by a white officer who mistook him for a suspect.
Sandgren defended himself Monday following his fourth-round upset of Dominic Thiem, saying: "Look, who you follow on Twitter I feel doesn't matter even a little bit. What information you see doesn't dictate what you think or believe. I think it's crazy to think that. I think it's crazy to assume that.
"That's not how information works. If you watch a news channel, you wouldn't then say that person who is watching the news channel thinks everything that news channel puts out. You wouldn't think that."
Another screengrab surfaced showing Sandgren using the word "disgusting" -- it was displayed by tennis writer Ben Rothenberg -- above a picture of Williams appearing to yell during a match against Roberta Vinci at the US Open in 2015.
With the social storm still swirling Williams wrote "turns channel" in a tweet Wednesday, seemingly referring to Sandgren's quarterfinal match.
Prior to taking questions from the media Wednesday, Sandgren read out a statement from his mobile phone.
"You seek to put people in these little boxes so that you can order the world in your already assumed preconceived ideas. You strip away any individuality for the sake of demonizing by way of the collective.
"With a handful of follows and some likes on Twitter, my fate has been sealed in your minds. To write an edgy story, to create sensationalist coverage, there are a few lengths you wouldn't go to to mark me as the man you desperately want me to be.
"You would rather perpetuate propaganda machines instead of researching information from a host of angles and perspectives while being willing to learn, change, and grow.
"You dehumanize with pen and paper and turn neighbor against neighbor. In so doing, you may actually find you're hastening the hell you wish to avoid, the hell we all wish to avoid.
"It is my firm belief that the highest value must be placed on the virtue of each individual, regardless of gender, race, religion or sexual orientation. It's my job to continue on this journey with the goal of becoming the best me I can and to embody the love Christ has for me, for I answer to Him and Him alone."
Sandgren later said he would "reflect" on where his "life has gone to."
"I'm going to go home and enjoy time with my family, turn off my phone, you know, just really reflect on the last two weeks, reflect where my life has gone to, where I'm at, where I am in this stage at 26, who I am as a person, who I want to continue trying to be, where I want to go in the sport, where I want to go as a man," he said.
"I constantly try to be introspective as to what's going on in my life. This has been a lot of information to digest in the last few weeks. So I need to take ample time to do so, so I can move forward correctly."