At 15 years, 338 days Pfeiffer is the fourth-youngest player ever signed to play in the NWSL. She has seen time with the U.S. National Teams at the U15, U16 and U17 levels. She played club soccer for St. Louis Scott Gallagher in the ECNL and was the ECNL U17 Player of the Year in 2023 as she helped her team win their 2nd straight national title. Her list of accolades also includes ECNL All-Conference and All-American honors for the 2021-2022 and 2022-2023 seasons.
