Alozie and Tarciane started Thursday when Nigeria faced an international football juggernaut, Brazil.
Two Houston Dash teammates - including one whom ABC13 Sports covered for her balance between the pitch and the cancer research lab - were official rivals in the Olympics on Thursday.
Tarciane and her Brazilian team won 1-0 over Michelle Alozie and her Nigerian team to open Group C play in the women's soccer tournament at the 2024 Paris Olympics.
Alozie, 27, and Tarciane, 21, started the match in their Olympics debut. Alozie was credited with a shot while Tarciane came away with a foul and a called offsides.
Ahead of the match in Bordeaux, France, the Dash posted a video message from Alozie to her teammate, which included a humorous attempt at speaking Portuguese.
"She taught me some Portuguese, and I forgot it," Alozie said with a smile, acknowledging that she faces a teammate in every major tournament she plays in. "I'm super excited to be her enemy out there and to go head to head with her, so good luck.
The Nigeria team selected Alozie for its 2023 FIFA Women's World Cup run, which included a faceoff with three of her Dash teammates on the Canadian side.
Nigeria's loss comes as part of a tough group that includes No. 9 ranked Brazil, seventh-ranked Japan, and first-ranked Spain.
Nigeria, the 36th ranked nation in women's soccer, faces Spain on Sunday and Japan next Wednesday. Brazil has Japan on Sunday and Spain next Wednesday.
Alozie and Tarciane want their teams to finish in the top two of their group or have the remaining two best third-place records of the three groups to advance to the knockout round.
The two women aren't the only Dash Olympians in France. Goalkeeper Jane Campbell didn't start in the United States' opening match on Thursday, a 3-0 victory over Zambia.
SEE MORE: In the lab: Houston Dash's Michelle Alozie has 'other' career at Texas Children's Hospital