In Portugal, Inglis's battalion was attached to the 2nd Division's 3rd Brigade under the command General Richard Stewart, an officer whose ill-health caused responsibility for the Brigade to fall to Inglis (who had recently been promoted to colonel) days before the Battle of Busaco on 27 September 1810 as Wellesley sought to inflict a defeat on André Masséna before withdrawing behind the Lines of Torres Vedras. The action was a success and Inglis performed well, retaining command of the brigade into the following year when the British army pursued the retreating Masséna. Inglis saw action during these operations in a skirmish at Pombal and action at Campo Mayor and Los Santos, when British forces withdrew from action in an attempt to surprise the French at the Battle of Albuera.