|Full name||Eduardo Alonso Álvarez|
|Date of birth||30 May 1974|
|Place of birth||Bilbao, Spain|
|Height||1.77 m (5 ft 10 in)|
|1996||→ Eibar (loan)||5||(0)|
|1997–1999||→ Salamanca (loan)||63||(4)|
|* Senior club appearances and goals counted for the domestic league only|
He spent the better part of his career with Alavés after starting out at Athletic Bilbao, playing 180 competitive matches for the former club. Overall, he made more than 200 appearances in both La Liga and Segunda División.
Born in Bilbao, Basque Country, Alonso was formed at Athletic Bilbao. He spent four full seasons in Segunda División with their B-team, making his debut at the age of 18 in a 4–0 home win against SD Eibar where he came on as a second-half substitute.
Alonso was loaned to precisely Eibar for the 1996–97 campaign, being recalled by his parent club shortly after. He first appeared in La Liga on 17 November 1996, starting in a 4–2 away victory over Sporting de Gijón.
After two years at UD Salamanca also in the top level – where he notably scored a goal for the hosts in a 2–1 home defeat of Athletic and another in a 1–1 draw to FC Barcelona at the Camp Nou the previous weekend– Alonso returned to San Mamés. He played 26 games across all competitions during the season, under manager Luis Fernández.
Following his release, Alonso represented fellow league sides UD Las Palmas and Deportivo Alavés, signing for the latter as a free agent after leaving the Canary Islands due to unpaid wages. He made his debut in the UEFA Cup on 31 October 2002 in a 1–1 home draw against Beşiktaş J.K. for the second round, going on to be relegated twice during his spell.
- "Goleada del Athletic en un derbi sin color" [Athletic routing in colourless derby]. Mundo Deportivo (in Spanish). 28 September 1992. Retrieved 7 March 2018.
- "Bronca y pañolada para un desacertado Sporting" [Boos and hankies for poor Sporting]. Mundo Deportivo (in Spanish). 18 November 1996. Retrieved 7 March 2018.
- "Edu Alonso y Corino hacen méritos para volver a casa" [Edu Alonso and Corino making all they can to return home] (PDF). Mundo Deportivo (in Spanish). 26 October 1998. Retrieved 7 March 2018.
- "Un tropiezo inexplicable" [Inexplicable fumble]. Mundo Deportivo (in Spanish). 18 October 1998. Retrieved 7 March 2018.
- "Edu Alonso: "El Alavés era mi principal opción, sin lugar a dudas"" [Edu Alonso: "Alavés was my first option, no doubt about that"]. Diario AS (in Spanish). 16 July 2002. Retrieved 7 March 2018.
- "Las Palmas quiere bajar la ficha a seis jugadores que no cobran hace meses" [Las Palmas want to revise contract to six players that have not been paid in months]. El País (in Spanish). 23 July 2002. Retrieved 7 March 2018.
- "Abelardo mantiene la esperanza" [Abelardo keeps the hope]. Mundo Deportivo (in Spanish). 1 November 2002. Retrieved 7 March 2018.
- "Edu Alonso se tiene que bajar el sueldo para irse de vacaciones" [Edu Alonso has to earn less in order to go on vacation]. El País (in Spanish). 23 July 2003. Retrieved 7 March 2018.
- "El Alavés negocia con Edu Alonso la rescisión de su contrato de dos años" [Alavés negotiate with Edu Alonso termination of his two-year contract]. El Correo (in Spanish). 1 August 2008. Retrieved 7 March 2018.
- "Edu Alonso se despide de la afición alavesista tras retirarse del fútbol" [Edu Alonso says goodbye to Alavés fans after retiring from football]. Marca (in Spanish). 12 September 2008. Retrieved 7 March 2018.
- "España se impone a Italia con un gol de Christiansen" [Spain down Italy with Christiansen goal]. Mundo Deportivo (in Spanish). 29 April 1993. Retrieved 7 March 2018.
- "Los 'Sub-21' de España y Noruega empatan a uno" [Spain and Norway's ‘Under-21’ draw one all]. Mundo Deportivo (in Spanish). 8 September 1993. Retrieved 7 March 2018.
- "Basque XI 0–1 Wales". BBC Sport. 21 May 2006. Retrieved 7 March 2018.