An effective method for applying eccentric (negative) overload is using the power rack eccentric potentiation method (PREP). The setup and application is simple.
Set the safety pins in the power rack just slightly above chest height. Load the bar with 110-120% of your 1RM and perform the eccentric portion of the bench press in a controlled fashion while gently letting the weight settle to the safety pins.
Next, you can slide out of the rack and strip a plate off the bar (representing a 20-30% reduction in load), or have spotters do it. Then press the weight back up and rack it. Put the plate you removed back on, slide back into the bench, and again lower it. Repeat this sequence for the desired number of reps, as demonstrated by my NFL athlete Bryce Canady in the video.
Besides being one of the safest ways to eccentrically overload your bench press, this technique also creates a level of post activation potentiation on the concentric phase. That's because the nervous system is hyper-activated from the supramaximal eccentric, causing the concentric phase to feel light and powerful. In fact, some athletes find they can handle heavier loads than normal on the concentric phase.