On 11 February, Napoleon turned the bulk of his army west toward Montmirail. He hoped to catch and destroy Sacken's corps between his army on the east and MacDonald's corps to the west at Meaux. Sacken's soldiers made a night march east toward Montmirail. Though Yorck urged his ally to retreat toward Château-Thierry, Sacken remained unaware of his danger and determined to fight what he believed was a weak enemy force. In the event, MacDonald had broken the Trilport bridge over the Marne, preventing him from striking Sacken's corps from the west. Delayed by the muddy roads, Yorck's tired troops were approaching Montmirail from the north, but still out of touch with Sacken. Napoleon barely managed to interpose some French soldiers at an important road intersection between the two Allied corps.