In February 1939, Juan Frutos Rubio served in Grupo 2-G-3, which was equipped with Fiat CR.32s

On 9 February, five I-15s were claimed by Spanish pilots near Peñarroya, in Andalusia. Two were credited to capitán Arístides García López (8-E-3), taking his overall tally to 17, and one each to Frutos Rubio, teniente Antonio Manrique (1-E-3) and teniente Luis Alcocer - the latter two pilots each ‘made ace’ with these successes.
This was the last aerial combat for the CR.32 in Spain

In 1942, he served in the Spanish expeditionary squadron in Russia.

At 16:40 on 1 July 1942, capitán Frutos Rubio of 15. (Span)/JG 27 claimed a LaGG-3 at low altitude (10m) at Tschleykowo.

At 08:45 on 9 October, capitán Frutos Rubio of 15. (Span)/JG 21 claimed a Pe-2 at 3000m 1km south-west of Kammskoye.

Frutos Rubio ended the war with 1 biplane victory and a total of 3.

Claims:

Kill no.	Date	Time	Number	Type	Result	Plane type	Serial no.	Locality	Unit
	1939
1	09/02/39		1	I-15 (a)	Destroyed	CR.32		near Peñarroya	2-G-3
	1942
2	01/07/42	16:40	1	LaGG-3	Destroyed	Bf 109		Tschleykowo	15. (Span)/JG 27
3	09/10/42	08:45	1	Pe-2	Destroyed	Bf 109		1km SW Kammskoye	15. (Span)/JG 51

Biplane victories: 1 destroyed.
TOTAL: 3 destroyed.
(a) Five I-15s were claimed by Spanish pilots. These were the last CR.32 claims in Spain.

Sources:
Air War over Spain - Jesus Salas Larrazabal, 1974 Ian Allan Ltd, Shepperton, Surrey, ISBN 0-7110-0521-4
Fiat CR.32 Aces of the Spanish Civil War - Alfredo Logoluso, 2010 Osprey Publishing, Oxford, ISBN 978-1-84603-983-6
Wings Over Spain - Emiliani Ghergo, 1997 Giorgio Apostolo Editore, Milano
Additional information kindly provided by Ondrej Repka.