Cureently there's a disturbing trend emerging in slams,where matches are easily going over 5 hours.In 80s and 90s this rarely happened,but due to advent of new technologies and improved athletism of the players,they are able to grind out our for longer periods..So here's my Solution: 1 Limit/Cap the number of RALLIES in Grandslams. 2 In Wimbledon Rallies should be restricted to 15 and 20 in other slams(AO,RG,USO).If rallies go over the aforesaid numbers,the Recieving player shall automatically be defaulted and the point shall be awarded to the person serving. It will help in solving following purpose: 1 Due to improevement in Medical Science,the players fitness have imroved tremendously so they can grind out for longer period, and due to invention of Poly strings they are already getting an unfair advantage,so it will help in achieving a parity between the things. 2 Longer rallies have a cascading effect on the players,for example-if they play a 30 ball rally,firstly they take around 40-50 seconds for the rally itself and then they take nearly that much time to rest and to play the next point.. This coupled with the recent changes in rules if enforced properly will help in reducing the time span of matches..Just a thought Guys!