The technology is being trialled at New York Red Bulls' stadium, with a video assistant referee taking 30 seconds to review a challenge in a Red Bulls II match against Orlando City.
A screen at the side of the pitch helped the officials decide to dismiss Orlando's Conor Donovan for denying a goalscoring opportunity just outside the penalty area.
Video replays will be used to advise on "game-changing" decisions in United Soccer League matches - the third tier of US football. That includes goals, red cards, mistaken identities and penalties.
They will also be tested in six other countries in the next two years, including Germany and Italy.
The game's lawmakers, the International Football Association Board (IFAB), wants to decide by 2019 on whether to introduce video replays across the sport.

Failed leadership candidate Lisa Duffy was having dinner with her staff in Bournemouth on Friday.
No action was taken against the curry house, which had completed pre-employment checks.
UKIP has long campaigned for tougher border controls to cut illegal immigration.
Jay Beecher, a spokesman for Ms Duffy, said: "Watching our chef running away into the night, his apron flapping in the wind, was a surreal moment.
"Politics can sometimes be such a stale and serous affair, so you have to see the funny side of things.
"In this case too, I couldn't help [but] be tickled by the irony."
The Border Agency questioned staff about their right to work and live in the UK.
Diane James was elected ahead of Ms Duffy to succeed Nigel Farage as the UKIP's new leader on Friday.

Pan gyhoeddwyd canlyniad y bleidlais gyhoeddus ym Mrwsel nos Fawrth, fe ddaeth Derwen Brimmon - coeden tua 500 mlwydd oed ger Y Drenewydd - yn ail i goeden 650 oed yn Wisniowa yng Ngwlad Pwyl.
Cafodd y goeden Bwylaidd 1,400 yn fwy o bleidleisiau.
Yn ystod yr Ail Ryfel Byd fe gafodd y goeden honno - Derwen Josef - ei defnyddio fel lloches gan deulu o Iddewon oedd yn cuddio rhag y Natsïaid.
Daeth Derwen Brimmon yn amlwg yn y newyddion pan gafodd llwybr ffordd osgoi'r Drenewydd ei newid er mwyn gwarchod y goeden hynafol yn dilyn ymgyrch gan bobl yr ardal a thu hwnt.
Cyhoeddodd Llywodraeth Cymru ar y pryd y byddai'r llwybr yn symud 15 metr o fonyn y goeden er mwyn peidio aflonyddu ar y gwreiddiau.

Lara Clarke, an amateur baker from the West Midlands, has baked this special Harry Potter cake.
In the past she has also baked the Weasley's flying car and the Hogwart's library.
Many other bakers around the world have also made cakes to celebrate JK Rowling's special day.
Video replays were used for the first time to send off a player for a professional foul in a Major League Soccer reserve match.
[NEXT_CONCEPT]
Immigration officials raided an Indian restaurant during a UK Independence Party conference dinner, sending the chef "running into the night".
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Mae coeden dderw hynafol wedi dod yn ail yng nghystadleuaeth Coeden Ewropeaidd y Flwyddyn 2017.
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The author of the Harry Potter books, JK Rowling, is celebrating her 50th birthday today.