CBS's new sitcom Rules of Engagement, starring Patrick Warburton, Megyn Price, and David Spade got off to a solid start Monday night as it recorded a 9.6 rating and a 15 share to place first in the 9:30 p.m. time period. The program was able to hold on to 84 percent of the audience for its lead-in, the top-ten hit Two and a Half Men, versus 79 percent for the recent occupant of the 9:30 p.m. slot, The New Adventures of Old Christine.