By this time, tensions had started appearing among the English generals, particularly between Pembroke and Chandos. This was based on their vastly different social status; as Jonathan Sumption put it, Pembroke "may have had the grander name but his inexperience showed." Although Chandos had by now been appointed Seneschal of Anjou, Pembroke—with what a biographer terms "aristocratic arrogance"—refused to serve under Chandos, who was, Richard Barber reminds us, only a banneret. It is possible that Pembroke was acting under the advice of his council, but either way, their armies were kept separate from each other on account of this. As a result, that October (or, says Sumption, December) he invaded Anjou with just his own force of 300 lancers on a fire-raising raid to Puirenon. Pembroke spent long enough there to attract attention; he was ambushed by Louis de Sancerre or Jean de Bueil (both commanded the French forces to the east of the Loire) and about 600 men: "Pembroke's men were still struggling to form lines across the village street when the French horsemen charged into them." About 100 of Pembroke's men were killed or captured, and he left behind a quantity of supplies, horses and materiel. Not only was he unable to fight the attacking force off, but, having escaped to a house at the edge of the village, Pembroke was forced to call upon Chandos for his assistance "In revenge," says Cokayne in his "Complete Peerage", he attacked the town again, before being despatched to relieve Belleperche, in early 1370, where he raised the French siege. At the same, Pembroke's own agents had recruited 300 men in England to join his force, and they were soon due to sail.