The Phillies’ rotation is set. For spring training, at least. Since John Lannan signed with the Phillies back in December, it’s been common knowledge who would fill out the five starting spots on the pitching staff. No difficult math or figuring there. But, what has been up in the air is the order they’ll file into, specifically the top three. There is no need to mention the credentials of Cole Hamels, Roy Halladay and Cliff Lee. There are World Series MVP awards and Cy Young honors to explain that. But who gets the nod on Opening Day? Hamels, the star of the staff last year, a season that earned him a $144 million contract? Halladay, the workhorse who has started the last three Opening Day games for the Phillies? Or Lee, long considered a top-five pitcher in baseball who had an outstanding season last year as well, despite poor support from the Phillies offense? Phillies coaches don’t seem too worried about it. They won’t say much, either, with April 1 still a month and a half away. But on Tuesday, in the Bright House Field clubhouse, the rotation for the first week of spring training games was posted. Hamels will start the Phillies’ first game, Saturday against the Astros. Halladay will follow on Sunday and Lee will pitch Monday’s game. Pitching coach Rich Dubee was coy when asked if that’s the order fans could expect to begin the 2013 campaign. “I’m not saying that,” Dubee said Tuesday. It’s easy to read between the lines. Both Dubee and Phillies manager Charlie Manuel have said they want to split the two lefties — Hamels and Lee — of the trio to balance things out. That would mean either Hamels or Lee starts Opening Day.