On the 18th of November, 1810, Masséna had completed the movement to the rear which he had commenced on the 14th. His army no longer threatened the Lines of Torres Vedras: he had abandoned the offensive for the defensive. Concentrated in the triangle Santarem-Punhete-Thomar, with his three corps so disposed that a march of twenty miles would suffice to concentrate everything save outlying detachments, he waited to see whether his enemy would dare to attack him; for he still hoped for a battle in the open field, and was prepared to accept its chances. At Bussaco, so he reasoned, his defeat had been the result of an over-bold attack on a strong position. The event might go otherwise if he threw the responsibility of the offensive on Wellington. He had secured for himself an advantageous fighting-ground: his left flank was protected by the formidable entrenchments around Santarem; his front was covered by the rain-sodden valley of the Rio Mayor, which during the winter season could be crossed only at a few well-known points. His right wing could not be turned, unless his adversary were ready to push a great force over villainous roads towards Alcanhede and the upper course of the Rio Mayor. And if Wellington should risk a large detachment in this direction, it might be possible to burst out from Santarem, against the containing force which he would be compelled to leave on the banks of the Tagus, about Cartaxo, and to beat it back towards the Lines--a movement which would almost certainly bring back the turning column from the North. For the English general could not dare to leave Lisbon exposed to the chances of a sudden blow, when there was little but Portuguese militia left to occupy the long chain of defensive works from Alhandra to Torres Vedras. For some weeks after his retreat to his new position at Santarem, Masséna lived in hopes that Wellington would either deliver an attack on his well-protected front, or undertake the dangerous turning movement towards his left.