Matthew Lawrence's injury-time equaliser earned a point for Crystal Palace in a 2-2 draw that leaves Sheffield Wednesday in relegation trouble.
Wade Small's second-half strike looked to have handed Wednesday victory and condemned Eagles boss Neil Warnock to a miserable return to the Steel City.
Teenage Chelsea striker Ben Sahar had put Wednesday ahead after 18 minutes before Ben Watson drew Crystal Palace level five minutes before the break.
Winger Small stuck in clinical fashion with 22 minutes remaining but Eagles defender Lawrence struck late on, lashing the ball home following Watson's corner to ensure Warnock had the last laugh.
Earlier, Clinton Morrison had struck the crossbar for the Eagles, while Sean McAllister also struck the bar with a 25-yard strike in terrible conditions at Hillsborough.