Rayo Vallecano is returning to La Liga after a 2-0 win against Girona on Sunday.
The Madrid club won the two-game promotion playoff 3-2 on aggregate after losing 2-1 at home in the first leg. Rayo played in La Liga in 2018-19 but was relegated after finishing last in the 20-team standings.
It won Sunday despite playing with 10 men from the 56th minute after defender Emiliano Velazquez was sent off with a second yellow card.
Alvaro Garcia and Oscar Trejo scored Rayo's goals in the first half.