At last year's All-Star Game, 12 of the 16 starting position players at Busch Stadium met that criteria.
The most intriguing battle between up-and-coming and established is playing itself out at third base in the AL, where the Rays' Evan Longoria cushioned his lead over the Yankees' Alex Rodriguez and was leading by nearly 300,000 votes as of Tuesday.
The 34-year-old A-Rod has made 12 All-Star Game appearances and has started five of the past six Midsummer Classics at the hot corner since moving to third base in 2004. But the 24-year-old Longoria, who went to the All-Star Game his first two years but has yet to start, is pacing the team with the best record in baseball with a .316 batting average, 10 homers and 42 RBIs entering Friday's game at Texas. A-Rod, meanwhile, has eight hits in his past 17 at-bats and is catching up to Longoria in the numbers department, batting .300 with eight homers and 43 RBIs.
Will he catch up to the youngster in voting, too?
Those looking for some of the best young talent around can take a good look at the National League outfield, where 26-year-old Ryan Braun led at his position and the 20-year-old Heyward was fifth, about 56,000 votes shy of a top-three spot as of Wednesday.
Braun ranks third in the NL with a .319 batting average, and Heyward is a favorite for the league's Rookie of the Year Award. But can 38-year-old, 12-time All-Star Manny Ramirez, who's struggling with a .273 batting average and just four homers, climb the ladder from ninth in voting -- where he stood on Wednesday -- to a top-three spot?
And can Ivan Rodriguez make it on the NL's roster as a 38-year-old starting catcher?
The first-year Nationals backstop is on the disabled list with a lower back strain but is expected back next week. Pudge, a 14-time All-Star, sports a .325 batting average that bests leading vote-getter Yadier Molina (.259) and the second-place Carlos Ruiz (.311).
But it looks like the wily veteran will have to keep up that pace when he returns if he wants to move up two spots.
Meanwhile, 10-time All-Star Derek Jeter doesn't look to be going anywhere. The 35-year-old was one of four Major Leaguers with more than a million votes as of Wednesday and he had the second-largest first-place lead in the AL, topping second-year shortstop Elvis Andrus of Texas by more than 500,000 votes.
But the largest lead in the Junior Circuit was a case of the young ousting the, well, experienced. The Twins' Joe Mauer, the reigning AL Most Valuable Player and 27 years old, was leading the Majors in votes, with 38-year-old Jorge Posada of the Yankees -- a five-time All-Star -- more than 700,000 votes back at catcher when AL results were made public on Tuesday.
In the AL outfield, 36-year-old and nine-time All-Star Ichiro Suzuki of the Mariners was the leading vote-getter on Tuesday thanks to a current .342 batting average, but 28-year-old Carl Crawford of the Rays ranked third and sat only about 70,000 votes back.
And then there's the intriguing battle at third base in the NL, where a 34-year-old Placido Polanco of the Phillies is currently beating out a 27-year-old in David Wright of the Mets. Polanco hasn't been an All-Star since 2007 and hasn't been a full-time third baseman since 2002. On Wednesday, though, his .306 batting average was enough to sport about a 123,000-vote lead over Wright, who has been to the All-Star Game each of the past four years and is hitting .267 with nine homers in 53 games.
But fans have until July 1 at 11:59 p.m. ET to vote. In the end, how much youth will be served, and how often will seniority prevail?