Blagge then attached himself to the Henry Howard, Earl of Surrey, a friend of Wyatt and a distinguished poet. Surrey was the son and heir of Thomas Howard, 3rd Duke of Norfolk, one of the most powerful magnates in the land. Blagge was the earl's senior by a few years and was not afraid to rebuke him for his erratic behaviour – a fact noted by Millicent Arundel, a witness before the Privy Council when, in March 1543, it investigated and punished Surrey's and Thomas Wyatt the Younger's rioting in London, which involved shooting in the streets as well as glass breaking. In July of that year English forces under Sir John Wallop were sent to support Imperial forces in defence of the Low Countries on the northern front of the Italian War of 1542–1546, moving out of the Pale of Calais. Blagge accompanied Surrey, taking 12 infantry from Kent on the expedition. He and Sir George Carew were nearly killed by sniper fire when they were inspecting a forward trench at the siege of Landrecies, a town occupied by the French early in the campaign. Both Surrey and Blagge gained considerable credit from their courage in the fighting. A letter of September 1543 from Sir Ralph Vane to Knyvet shows that Blagge was known by his comrades by the pet name Tom Trubbe. Blagge was again listed as part of the Kent contingent in 1544. His war service was probably a contributory factor when, on 11 March 1544, Blagge, the "King's servant," was granted the stewardship of the manor of Maidstone. However, the post had previously been held by his friend, Thomas Wyatt and the terms of the grant made clear that Blagge was appointed in his place.