An old baseball phrase. It described the pitching staff of the old Boston Braves: their top two starting pitchers Warren Spahn and Johnny Sain were of hall-of-fame calibre, but their other starters often drew major-league paychecks under false pretenses - better to have their games rained out. Variations, if you're bored: "Sain, and pray for a hurricane", when Spahn was gone, or modern-day "Pete (Pedro Martinez) and Bret (Saberhagen), and pray for wet", for the Red Sox.