JL1985
Striker
I did have a look through the years as to when the mens champion started and as you say, Novak and Wawrinka both started on Monday but Nadal started the previous 2 years on the Tuesday.He's lucky Fabio couldn't keep that level up for another set because there was only one winner if he did.
Not sure if there's a strict rule about when they play but I'm 99% sure Djokovic played on the Monday last year and the Wawrinka - Rosol five setter the year before was a Monday as well.
I think they normally have a French player as the main attraction on the men's side on the Sunday I think.