Mark O'Neill
Defender · Seattle Sounders · №40
Recent matches
| Date | Match | Score |
|---|---|---|
Seattle Sounders
Guadalajara Chivas
Leagues Cup
|
1:2 | |
Seattle Sounders
Querétaro
Leagues Cup
|
3:0 | |
Toluca
Seattle Sounders
Leagues Cup
|
3:0 |
Season statistics
| Competition | Season | Games |
|---|---|---|
| Leagues Cup | 2026 | 3 |
About the player
Mark O'Neill's path into Major League Soccer ran through college football rather than a club academy. Between 2020 and 2024 he combined studies at Creighton University with appearances for Vermont Green FC in USL League Two, including a run in the 2024 US Open Cup.
The breakthrough came at Vancouver Whitecaps FC 2 in 2025, where O'Neill made 27 appearances and scored nine goals. He signed a first-team contract with the Whitecaps that September and was part of the Vancouver squad that won the Canadian Championship the same year.
His time in Vancouver's first-team squad was short. In February 2026 O'Neill joined Tacoma Defiance, Seattle Sounders' MLS NEXT Pro affiliate, as a free agent. He made 20 appearances there in the 2026 season, scoring once and setting up three goals, before a shortage of available players led Seattle to sign him to the first team on a Short-Term Agreement that August. He featured in the Leagues Cup, coming on as a substitute against Querétaro on 9 August.
O'Neill has not been capped by the United States national team. In Seattle, the surname is not new: his older brother, Shane O'Neill, previously played for the Sounders.
