A-Rod sets record pace, but can he maintain it?

The career of just about every great slugger traces the arc of a home run: It takes off with breathtaking power and swiftness, levels off late in flight and then falls precipitously.

Alex Rodriguez took off faster than any ballplayer in history, but the hardest part of his journey may just be beginning.

Rodriguez homered twice Wednesday night in Milwaukee to lock up a win over the Brewers and in the process, at age 29, became the youngest ballplayer to reach the 400-home run plateau.

It wasn't a big deal in these jaded times. Not even for the Yankees.

They've got enough problems with an old-looking pitching staff, wins in only two of their last 11 games and owner George Steinbrenner breathing down their necks.

Rodriguez got a polite standing ovation from Milwaukee fans in the eighth inning, a few forearm bashes on his return to the dugout, a souvenir photo holding the bat and ball afterward and this brief tribute from manager Joe Torre:

"That's pretty incredible," said Torre, who watched the highlight shot from the clubhouse after getting tossed for arguing a few innings earlier. "The shape he's in, the way he works, who knows where he's going."

For baseball's sake, it better be far. In this, the first season of steroid withdrawal, it's hard to find a better name to pencil in atop the homer list. And the longer he stays there, the better.

Rodriguez isn't muscle-bound or old. Yet. And he's untainted by steroids. So far.

He'll only have to average 35 home runs for the next 10 years and he's home free. By now, enough people have crunched the numbers to provide a frame-by-frame reference of how hard that will be. For starters, look at what injuries did to Ken Griffey Jr., whose career home-run pace Rodriguez just passed, and the picture comes into sharp focus.

To minimize wear and tear and cut down on collisions, Rodriguez is going to have to leave the infield. The top 10 spots on the all-time list -- from No. 1 Henry Aaron to 10th-place Rafael Palmeiro -- are claimed by outfielders, first basemen or part-time designated-hitters. That's not a coincidence.

And Rodriguez may have to bail out of New York, where the attention and pressure add to the distance of the fence in left-center.