Question: which spanish team founded in 23 August 1923 was relegated to Tercera División.

Context articles: 2009 Segunda División B play-offs
2014 Segunda División B play-offs
1977–78 Segunda División B
Celta de Vigo
2012 Segunda División B play-offs
2011 Segunda División B play-offs
2007 Segunda División B play-offs
1929 Segunda División
2013 Segunda División B play-offs
2006 Segunda División B play-offs

The 2009 Segunda División B play-offs (Playoffs de Ascenso or Promoción de Ascenso) were the final playoffs for promotion from 2008–09 Segunda División B to the 2009–10 Segunda División.
 The four first placed teams in each of the four Segunda División B groups played the "Playoffs de Ascenso" and the four last placed teams in Segunda División were relegated to Segunda División B.
 It also decided the two teams which placed 16th to be relegated to the 2009–10 Tercera División.
The 2014 Segunda División B play-offs (Playoffs de Ascenso or Promoción de Ascenso) are the final playoffs for promotion from 2013–14 Segunda División B to the 2014–15 Segunda División.
 The four first placed teams in each of the four Segunda División B groups join the "Playoffs de Ascenso" and the four last placed teams in Segunda División will be relegated to Segunda División B.
 It also decides the teams which placed 16th to be relegated to the 2014–15 Tercera División.
The 1977–78 Segunda División B was the first season of Segunda División B, the third highest level of the Spanish football league system.
 The league was made up of last 4 teams from 1976-77 Segunda División and 2nd to 10th teams from 1976-77 Tercera División.
 In concept, the Segunda División B was identical to the old Tercera Division, which was now reduced to two divisions.
 First and 2nd in each group were promoted to Segunda División, and the bottom three were relegated to the Tercera División.
Real Club Celta de Vigo (] ; "Royal Club Celta de Vigo"), commonly known as Celta Vigo or simply Celta, is a Spanish professional football club based in Vigo, Galicia, currently playing in La Liga.
 It was founded on 23 August 1923 following the merger of Real Vigo Sporting and Real Fortuna Football Club.
 Nicknamed "Os Celestes" (The Sky Blues), they play in sky blue shirts and socks along with white shorts.
 The club's home stadium is Balaídos, which seats 29,000 spectators.
 Celta's name is derived from the Celts who were once present in the region.
 Its main rival is fellow Galician club Deportivo de La Coruña, with whom it contests the Galician derby.
The 2012 Segunda División B play-offs (Playoffs de Ascenso or Promoción de Ascenso) were the final playoffs for promotion from 2011–12 Segunda División B to the 2012–13 Segunda División.
 The four first placed teams in each of the four Segunda División B groups played the "Playoffs de Ascenso" and the four last placed teams in Segunda División were relegated to Segunda División B.
 It also decided the two teams which placed 16th to be relegated to the 2012–13 Tercera División.
The 2011 Segunda División B play-offs (Playoffs de Ascenso or Promoción de Ascenso) were the final playoffs for promotion from 2010–11 Segunda División B to the 2011–12 Segunda División.
 The four first placed teams in each of the four Segunda División B groups played the "Playoffs de Ascenso" and the four last placed teams in Segunda División were relegated to Segunda División B.
 It also decided the two teams which placed 16th to be relegated to the 2011–12 Tercera División.
The 2007 Segunda División B play-offs (Playoffs de Ascenso or Promoción de Ascenso) were the final playoffs for promotion from 2006–07 Segunda División B to the 2007–08 Segunda División.
 The four first placed teams in each of the four Segunda División B groups played the "Playoffs de Ascenso" and the four last placed teams in Segunda División were relegated to Segunda División B.
 It also decided the two teams which placed 16th to be relegated to the 2007–08 Tercera División.
The 1929 Segunda División Grupo A season saw 10 teams participate in the second flight Spanish league.
 There was no team promoted to Primera División.
 Celta and Racing de Madrid were relegated to Tercera División.
The 2013 Segunda División B play-offs (Playoffs de Ascenso or Promoción de Ascenso) were the final playoffs for promotion from 2012–13 Segunda División B to the 2013–14 Segunda División.
 The four first placed teams in each of the four Segunda División B groups played the "Playoffs de Ascenso" and the four last placed teams in Segunda División were relegated to Segunda División B.
 It also decided the three teams which placed 16th to be relegated to the 2013–14 Tercera División.
The 2006 Segunda División B play-offs (Playoffs de Ascenso or Promoción de Ascenso) were the final playoffs for promotion from 2005–06 Segunda División B to the 2006–07 Segunda División.
 The four first placed teams in each of the four Segunda División B groups played the "Playoffs de Ascenso" and the four last placed teams in Segunda División were relegated to Segunda División B.
 It also decided the one team which placed 16th to be relegated to the 2006–07 Tercera División.