[6] He then moved to Madrid FC where he played from 1931 to 1936, scoring 53 goals in 92 matches;[7] from 1932 onwards, his teammates included his younger brother Pedro.

In its place Regueiro, was chosen to be captain of the Basque national football team for its tour of Europe.

[8] Later, in the 1938–39 season, he and most of the Basque team played under the name CD Euzkadi in Mexico, before moving to other local clubs, Asturias F.C.

[10] Regueiro played 25 times for the Spanish national team, including participating in the World Cup in Italy in 1934 and the 1928 Olympic games.

[11] Later he played 40 times for and captained the Basque national team during its tour of Europe and the Americas.