Eight CR.32s from 2-G-3 and six from 3-G-3 took off in the morning on 31 May. Their task was to escort a number of Ju 52/3ms and Ro.37s over the La Puebla de Valverde sector.
On arrival, they encountered 22 Chatos and 22 Ratas. A 90-minute clash began immediately but the Nationalist crews were successful in protecting the bombers, which, their task completed, made good their escape.
Eight I-15s and two I-16s were claimed shot down without losses. The successful pilots were teniente de Hemricourt (2-E-3) (I-15), teniente Julio Salvador (CO 1-E-3) (three I-15s and one I-16), teniente Rafael Simón García (2-G-3) (I-15), teniente Manuel Vázquez Sagastizábal (1-E-3) (I-15), capitán Javier Murcia Rubio (3-E-3) (two I-15s) and Muerza (I-16).
Teniente Salvador’s first I-15 was seen falling close to La Puebla, the pilot of the second escaped by parachute into Republican territory and the third, flown by teniente Juan Sayós Estivill of 1^a Escuadrilla, made an emergency landing at the Republican airfield of Sarrión with a damaged engine. Estivill quickly abandoned his fighter, which was strafed by Salvador until it caught fire and burnt out. A few minutes later the Spanish ace destroyed an I-16. Teniente de Hemricourt shot down another I-15 near La Puebla, the Belgian watching his opponent take to his parachute and land in the Republican zone.
During this combat, capitán Ángel Salas was attacking a Chato when three enemy fighters in turn attacked him. His Fiat was hit several times before he managed to break away from the attack, but his machine was vibrating so badly that he had to return to base.
Bf 109s escorting Legion Condor bombers also engaged some of the I-16s.
The Republican bulletin issued the following day acknowledged the loss of five aeroplanes that crashed within its own lines, with four wounded pilots and one uninjured. The Polikarpov units had claimed the destruction of 12 Italian and German aircraft in return, although not a single Nationalist aircraft had actually been lost in combat. The Escuadra de Caza N^o 11 claimed ten CR.32s and it seems that Vladimir Bobrov of the 1^a/21 (I-16) claimed one of the CR.32s.

In the end of June 1938, Joaquín García Morato assumed command of the second Fiat group (3-G-3).
Pilots in Escuadrilla 3-E-3 (later 5-E-3) were:
Capitán Javier Murcia Rubio (CO)
Ignacio Alfaro Arregui
G. Queipo de Llano Martí
Andrés Robles Cebrián
Joaquín Chapaprieta Inglada
Alfonso Rubial
García de Juan

Pilots in Escuadrilla 4-E-3 (later 7-E-3) were:
Capitán Heraclio Gautier Larrainzar (CO)
Teniente Joaquín Velasco Fernández Nespral
Teniente Emelio O’Connor Valdivielso
Acuña
Fernando Arrechea Belzunce
Enrique Munaiz de Brea
Alférez Alonso Fariña

Pilots in the Escuadrilla 6-E-3 were:
Capitán Jose Barranco del Egido (CO)
Teniente José Larios y Fernández Villavicencio
Muerza
Lacour
R. Bartolomé Chávarri
Kindelán
Carracido P. Téllez Rivas

Muerza ended the war with 1 biplane victory.

Claims:

Kill no.	Date	Time	Number	Type	Result	Plane type	Serial no.	Locality	Unit
	1938
1	31/05/38	morning	1	I-16 (a)	Destroyed	CR.32		La Puebla de Valverde area

Biplane victories: 1 destroyed.
TOTAL: 1 destroyed.
(a) 2-G-3 and 3-G-3 claimed 8 I-15s and 2 I-16 without losses. The Legion Condor didn’t claim nor lost anything. The Republicans claimed 12 Italian and German aircraft for the loss of 5 aircraft (4 wounded pilots).

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
Additional information kindly provided by Alfredo Logoluso and Ondrej Repka.