We were going for an evening ascent of the 2-pitch route Malbogies in Avon gorge. My partner lead the first pitch uneventfully. I (somehow) split a tip on second but otherwise arrived unscathed at the first belay. We re-racked and I started the second pitch. Made it to the start of the leftwards traverse when a massive hold came off. I fell a few metres and was caught by a no.4 nut. (Another back-up nut that I'd failed to seat properly came out, unsurprisingly). The hold fell to the base of the route but fortunately no-one was around and my belayer was well out of harms way. I came to a stop holding onto the rock but hanging over the edge of an overhang below the slab I'd scraped down. Apart from superficial injuries I was ok, so I climbed back onto the slab, sorted out the ropes and finished the route, cautiously and with lots of protection.