As mentioned by others here...
Simply enable a clip gain envelope (I believe the shortcut is ctl-click-drag in a clip and the gain envelope appears)...
Then click-drag in the lower portion of the clip going from just before the peak to just after and finally click-drag down in the upper clip area of the marked zone... That will lower the gain of the clip for that portion before it hits the compressor. This will lower the gain of that portion as well as buy a bit of time for the attack to get moving to follow that starting peak...
Keni