Once upon a time, baseball was a dichotomized game: Both the American League and National League drew lines seldom crossed.

But the sport has become a mobile society, with trades and free agency homogenizing the leagues, a trend perhaps best dramatized by the campaigns to land starting berths in the outfield for the 80th All-Star Game.

Until relatively recently, making the starting lineups of both leagues at any position was a rarity. In fact, according to a quick check, no one had managed it until 1966, when the All-Star Game was 32 years old and Baltimore's Frank Robinson started in left field for the AL nine years after doing the same for the NL as a Cincinnati Red. (This distinction by Robinson was eclipsed by one more significant, when after that 1966 season he became the first player named MVP in both leagues.)

Now consider the turnover in the NL alone: Of the 11 different outfielders included in the 2005-08 All-Star starting lineups, four are now in the other league -- Matt Holliday, Ken Griffey Jr., Jason Bay, Bobby Abreu -- and another (Barry Bonds) has retired.

Naturally, some of the candidates to fill those NL shoes are transplants from the AL.

Leading among them is Raul Ibanez, whose adaptation to a new league is not unlike Robinson's impact 43 years ago.

Ibanez, who will turn 37 in two weeks, somehow avoided All-Star recognition during 13 seasons in Seattle, some of them quite exemplary (77 homers and 338 RBIs in 2006-08 alone).

He would appear to have blown his cover in Philadelphia, where he is batting .350 with 13 homers and 36 RBIs for the defending World Series champions. In the NL, those numbers rank sixth, second and second, in that order, making Ibanez the only player in either league to rate among the top six in all three departments.

"Every time he goes out there, you expect him to get a hit," Phillies starter Brett Myers recently said about Ibanez. "And when he makes an out, it's like, 'He's human.'"

A safe hunch is that Ibanez's top competition for the left-field slot will come from another ex-American Leaguer, perennial All-Star starter Manny Ramirez.

Ramirez is running a "covert" campaign. However, his current suspension does not disqualify him. There is no "recall" option for All-Star voting.

Besides, Ramirez's season had gotten off to another strong start (.348, with six homers and 20 RBIs in 27 games) when he was shut down for violating baseball's drug policy. And he is due to be reinstated around July 2, ideal timing for the Midsummer Classic on July 14 in St. Louis.

Of all the displaced National Leaguers, Boston's Jason Bay rates the most deserving chance to crack the AL outfield -- as, fittingly enough, Ramirez's replacement.

Bay's overall production is impressive enough -- .294 with 11 homers and 40 RBIs, the latter two tops among AL outfielders -- but his performance in the clutch is what really stands out. He is batting .333 late in close games, with three homers and seven RBIs.

The perception that the Red Sox cannot win without Bay, particularly given David Ortiz's power outage, is borne out by the numbers. He is hitting .354 in Boston's 22 wins, and .204 in its 16 losses.

Bay is joined in the hunt for a starting slot by a May-December scrum of worthy candidates.

Johnny Damon, despite a high-profile career only a two-time All-Star and one-time (2005) starter, is enjoying quite a rebound season in the Bronx, batting .327 with 10 homers and 28 RBIs. At 35, he is in double-figures in homers before the end of May for the first time in his 15-year career.

Torii Hunter, also a two-time All-Star and one-time (2002) starter, has picked up the Angels' offensive slack magnificently in the absence of Vladimir Guerrero, batting .317 with nine homers and 31 RBIs.

And there is no way to overlook Ichiro Suzuki, who rings up 200-hit seasons and All-Star starts with equal regularity.

The young end of the generational showdown is led by a pair of Orioles unjustly obscured by Baltimore's standing. Nick Markakis (.327-6-34) has continued the remarkable start of his career, and has now been joined by 23-year-old Adam Jones (.366-8-26).

Damon, always one of the most quotable and opinionated Yankees, recently toasted one of the competition, telling the Baltimore Sun that Jones is "very, very talented."

"The improvement we saw from the beginning of last year to now is staggering," Damon also said. "If he keeps this progression rate going, he's going to be at a few All-Star [Games]. If the Orioles put it together, he might even have a chance to challenge for MVP honors."

So is Tampa Bay's Carl Crawford, who is batting .329 and leading the Go-Go-Rays -- as well as the AL -- with 25 steals.

There is a stronger All-Star veteran presence among the leading NL choices -- not necessarily a great thing given the league's 12-year winless rut.

The senior member of the candidates -- the Mets' Carlos Beltran, a starter in 2005-07 -- is also the top performer, with his .364 average, six homers, 28 RBIs and sparkling defense.

Ryan Braun of the torrid Brewers is certainly in position to regain his '08 starting berth, batting .323 with eight homers and 29 RBIs. (NL) Central casting also promotes the Cubs' Alfonso Soriano (.279-12-25) and Carlos Lee (.324-8-29), who has led the Astros' resurgence.

Holliday, a starter last summer, has gone to the AL West (and, some would say, has also gone south with his .268 average for the A's). As for the third leg of the NL's 2008 starting outfield, the irony is that Kosuke Fukudome is having an infinitely stronger season (.325-4-17) than he was a year ago, when the celebrity of being the Cubs' pioneer Japanese player carried him at the ballot.

The NL West's standout "active" hope could be the Rockies' Brad Hawpe, batting .333 with six homers and 32 ribbies.