Javi Mier

Born in Oviedo, Asturias, Mier was a Real Oviedo youth graduate. He made his senior debut with the reserves on 2 September 2017, starting in a 1–0 Tercera División away win against TSK Roces. Mier scored his first senior goal on 13 May 2018, netting his side's only in a 1–2 loss at CD Llanes. He contributed with one goal in 14 appearances, as the B-side returned to Segunda División B after 16 years. Mier made his first team debut on 5 January 2020, starting in a 1–1 home draw against Málaga CF in the Segunda División. He scored his first professional goal on 3 January 2021, netting his team's first in a 2–2 home draw against RCD Mallorca. On 1 September 2023, Mier terminated his contract with Oviedo, and signed for fellow second division side SD Huesca the following day. On 23 June 2026, after Huesca's relegation, Mier joined Primera Federación side Real Murcia CF.

Mier is a youth international for Spain, representing the under-16s in 2014.

Club

As of match played 14 March 2021

Mier's twin brother Jorge is also a footballer who plays as a midfielder. Their older brother, Tato, was also an Oviedo youth graduate.