According to Buzzerblog and GSN's website, "Grand Slam" will only air new episodes on Saturdays for the second half of its run.
This week- Quarterfinals, Part 1
Aug. 25th- Quarterfinals, Part 2
Sept. 1st- Semifinals
Sept. 8th- Championship
Also, just before the Championship Show on Sept. 8th, a marathon of the first seven "Grand Slam" episodes will begin that day at noon.