The N.L. West Power System play is on Arizona at 9:40 eastern. The Diamond backs have won 4 of 5 at home vs Colorado and tonight they fit a solid system that is 11-1 and perfect in Division games for home favorites that are off a home dog loss and had 1 or no errors, vs an opponent off a home win and scored 4 or less and had 5 or more hits. Colorado is terrible on the road and has dropped 44 of 56 as a road dog and 5 of 6 with a day off. Gray is 0-5 on the road and Kelly for Arizona has won his last 5 as a home favorite and they have won his last 3 overall. Play on Arizona.