[2] He signed for Real Zaragoza two years later, playing 33 La Liga matches in every season he remained there and never netting less than 15 goals;[3] in his debut campaign, he scored five in an 8–1 rout of RCD Español.
[4] For the 1982–83 campaign, Alonso moved to FC Barcelona, being used frequently in his first year but losing his importance after the purchase of Scotland's Steve Archibald, and never regaining it again.
Still, he scored three goals against IFK Göteborg in the 1986 European Cup semi-finals, allowing the Catalans to reach the final of the competition against FC Steaua București in Seville,[5] where he came on as a substitute in extra time, in an eventual penalty shootout loss; he was one of four players that had his attempt saved by opposing goalkeeper Helmut Duckadam.
[6] Alonso regained his scoring prowess at Barça neighbours Espanyol, helping the side to finish third in his first season with 17 goals.
[8] He retired the following year at the age of 35, having won three caps for the Spain national team – his debut came on 21 December 1978 in a 1–0 friendly loss with Italy, in Rome.