OMAHA -- Buster Posey strode, twirling bat in hand, to the plate Friday morning for batting practice at Rosenblatt Stadium when a fan sitting behind the third-base dugout stood and screamed, "Posey, you're my hero."

If the Florida State catcher heard the would-be idolater, he never let on. He simply stepped into the batter's box and crushed one of the first pitches he saw, sending it the opposite way over the 375-foot sign in right-center field. He dropped the bat and trotted around the bases before heading out into the field to shag flies.

Jason Castro, meanwhile, had no such support from among the hundreds of fans that remained to watch Stanford's batting practice a few moments later. The Cardinal backstop was greeted with neither boos or cheers, but like Posey, he sprayed balls all over Rosenblatt's sun-drenched outfield before calling it a morning.

While both first-round Draft selections are worthy of any accolades that come their way, Friday morning's proceedings provide the continued impression that Posey is regarded as being just a tick ahead of his counterpart. The Giants selected Posey with the fifth overall selection in last week's First-Year Player Draft, but he was being considered by Tampa Bay almost up until the time the Rays made Tim Beckham the top selection.

The Astros grabbed Castro with the 10th overall pick, after the Marlins took high school catcher Kyle Skipworth with the sixth pick, and will look to make him one of the cornerstones in the effort to rebuild their Minor League system. Castro and Posey were on the field Saturday afternoon as the College World Series kicked off at Rosenblatt Stadium, launching the beginning of what some believe will be their simultaneous journey toward becoming the next pair of dominant catchers in the National League.

Though neither Posey nor Castro viewed the matchup between the Seminoles and Stanford as a personal showcase or competition with the other, it was Castro who ultimately had the upper hand, both at the plate and on the field, as Stanford rumbled past FSU, 16-5, in a game that lasted four hours, 11 minutes.

Castro went 1-for-5 while also reaching base on an error. His sixth-inning double helped fuel a rally and he also drove in a run with a bases-loaded walk in the seventh before reaching base on an error and scoring in Stanford's 11-run ninth inning.

Posey, meanwhile, went 1-for-4 with a walk, but struck out twice, including once with two men on in the fifth inning. He has also served as FSU's closer at times this season, appearing in eight games, collecting six saves and not allowing a run in 7 1/3 innings prior to coming into Saturday's game in the ninth inning with the score tied at 5. While John Gast, whom he relieved, took the loss, Posey allowed six runs. Five of them were unearned, though, the result of two errors by shortstop Tony Delmonico (sixth round, Dodgers).

Posey walked two and allowed two hits while throwing 27 pitches. His future, however, lies behind the plate, not throwing to it, regardless of how he's been used this year.

He said the last week or so has been "the biggest thrill of his baseball career." Still, both he and Castro have said they haven't given a thought to signing with their prospective franchises and won't until FSU and Stanford are finished at the CWS.

"It's just the way I'm handling it," Posey said. "I want to live in the moment and enjoy it. And Castro is a great player. I'm excited that he's here."

The left-handed-hitting Castro and Posey, who saw his average "fall" to .456 on Saturday, met last summer while playing on the same team in the Cape Cod League. They formed a friendship, shared some tips on catching and then went their separate ways, but will forever be linked by this Draft. While four spots separated them in the Draft, Castro says he has nothing to prove in terms of his ability when compared to Posey's.

"Buster is a great player and a great guy," said Castro, who is now hitting .376 with 70 RBIs. "He deserves everything he's getting. But it's not like I feel that I should have been taken over him. I'm happy to be where I am and happy to have been selected by the Astros.

"I think I might have taken people by surprise a little this year because I had a tough year last year [batting .167]. But I had a good season on the Cape [.341, 24 RBIs]. It was something I needed personally to get back on the right track. I always knew I was capable."

Castro also demonstrated on Saturday how well he could handle himself behind the plate. He picked Tommy Oravetz off first base in the sixth inning and caught Jason Stidham trying to steal third in the first. He did, however, allow a passed ball in the eighth.

Still, several Major League executives that scouted both players, who are among the three finalists for the Johnny Bench Award as college baseball's top catcher, extensively spoke to MiLB.com about the pair and they gave Posey a slight edge at this point.

"They have some similarities because they have played multiple positions," one executive said. "Castro played first base on the Cape and Posey has played shortstop and has been a closer. He's still relatively new to catching. I like them both and Castro's a nice guy, but I love Posey."

One other executive had this take on the duo.

"They are both very good receivers, hands-wise, but Posey clearly has the better arm, probably a grade higher," he said. "Castro's arm is just good enough. It's not a plus arm. But they both run a good game.

"I like them both, but Posey is clearly a grade better. Castro reminds me of Jason Jaramillo when he was at Oklahoma State. I wasn't crazy about Jaramillo. Maybe Castro will be better."

Maybe he will. He had the slight edge on Saturday, but the duo figure to have plenty more meetings in the years to come, meetings that will likely only add more fuel to the argument as to which player truly is better.