Z750 Clutch

The clutch on my '07 Z750 is no longer engaging. The lever pulls all the way back to the handlebars without resistance and I'm unable to change gears. All externally visible linkages appear to operate normally and it's a near new clutch cable. Over the last year or so the clutch friction point has moved progressively closer to the handlebars requiring incremental adjustment to the point where there is now no adjustability left. The bike itself has nearly 95,000km on the clock since I bought it new and has never missed a service. The clutch "failure" and loss of resistance occured this morning while changing into 4th gear at about 5000rpm during expressway riding (I'm a slow old fart and treat my bike with kid gloves as I'm not in any way mechanically inclined). Any ideas or suggestions would be greatly appreciated before I send it off to be repaired.