"There was only one way Randy Johnson could've sparkled on the mound Wednesday night: Walk onto the field and hold a 7-iron in the air.

Steady rain and occasional lightning made it impossible for Johnson to throw the first pitch in pursuit of his 300th career victory. Mindful of the milestone, the Giants and Washington Nationals waited until 10:47 p.m. EDT before relenting to a postponement. The game will be made up as a traditional doubleheader today at Nationals Park; Johnson will start the first game, which is scheduled to begin at 4:35 EDT.

But with more problematic weather in the forecast, both sides could be stuck in another holding pattern.

"For a game with a player going for a milestone, you want to have something more optimal," Giants president Larry Baer said. "The challenge now is to get two games in a 36-hour window. The league will require us to go as long as we have to."

Johnson occasionally peered into the flooded dugout to check conditions, but Giants Manager Bruce Bochy said the 45-year-old left-hander took the delay in stride.

"He was just trying to find out the weather updates," Bochy said. "Really, other than that, he was relaxed. He was just waiting to hear.

"He didn't waver (about starting), either. But I think it was finally starting to wear on him toward the end."

Johnson, who will be pitching on seven days of rest, will oppose Jordan Zimmermann in the afternoon game. Matt Cain and Ross Detwiler, who were scheduled to pitch Thursday, will start the second game.

Any logic to starting Johnson in the first game?

"Well, sure," Bochy said. "I don't want him sitting around after all the waiting today."

The doubleheader eventually will impact the Giants rotation. Assuming they complete both games today, the club would need a fresh arm — possibly recalling Billy Sadler from Triple-A Fresno -- to pitch Monday in Florida.

And if Johnson doesn't win No.300 in Washington, his next chance would come in a much more intriguing locale."