Lee's repulse of McClellan at Richmond gave the Southern armies new opportunities. Lee moved north, crushed a Federal army at Manassas again, and crossed north of the Potomac River. Southern armies also broke out of Tennessee to invade Kentucky. Now it was the South that looked to have victory within its grasp, but it was not to be. McClellan turned back Lee at Antietam, and Buell stopped the main Confederate army in Kentucky at Perryville in October. A wearisome stalemate prevailed.