For every highly rated prospect who rose quickly through a minor league system to make an immediate splash in the majors, such as Los Angeles Angels outfielder Mike Trout, there are two dozen stories of The Next Big Thing still waiting his turn.
Even as the 21-year-old Trout, the Angels' first-round pick in 2009, was already in the MLB All-Star Game this week, more seasoned prospects were anxiously awaiting their shot in the majors.
And, in their quest for constant improvement, MLB clubs are constantly checking minor league inventory in search of that key call-up who can change the course of history.
Teams in the pennant chase might not be willing to sell their top minor league assets for a rental player in the trade market such as Chicago Cubs right-hander Matt Garza, for whom the cost is likely to be prohibitive.
But the temptation to bring on a bona fide ace has tempted less likely buyers in the past -- Milwaukee's unexpected acquisition of pitcher C.C. Sabathia from Cleveland in July 2008 before he grabbed the cash from the New York Yankees in 2009, and, more recently, the Indians going all in to acquire pitcher Ubaldo Jiminez from Colorado in July 2011.
Bases on a survey by team correspondents for The Sports Xchange, here is a closer look at the top candidates to be the Next Big Thing for all 15 American League teams (listed alphabetically):
Baltimore Orioles -- OF Henry Urrutia
Urrutia wasn't even in professional baseball last season. This year, he spent the All-Star break in New York as a member of the Futures Game. Later this summer, the Cuban defector could be in the majors. The left-handed batting outfielder, 26, is on the doorstep, earning some seasoning at Triple-A Norfolk after a hot start with Bowie in his first pro season. He could be recalled to give the Orioles some boost at the plate and in the outfield.
Boston Red Sox -- SS Xander Bogaerts
Despite their lofty spot atop the AL East, the Red Sox already have called up several of their top prospects, including right-hander Allen Webster and shortstop Jose Iglesias. In the second half, starting pitcher Rubby De La Rosa could follow, especially if the Red Sox determine he can help out of the bullpen. The real headliner, however, would be if the Sox decide to call up top prospect Bogaerts, who recently was promoted to Triple-A Pawtucket. Bogaerts, only 20, could be in line for a taste of the majors once rosters expand in September.
Chicago White Sox -- SP Erik Johnson, CF Jared Mitchell
Josh Phegley was already called up and quickly established himself as a superior catcher to failing Tyler Flowers. The selling off of veterans will open the floodgates further, and likely very soon. Starting pitcher Erik Johnson, their top pitching prospect, is expected by August and former first-round pick Jared Mitchell could get a look just to see what he can do at the major-league level.
Cleveland Indians -- SP Danny Sanchez
In his major league debut on July 11, the right-handed Salazar had the most electrifying start of the first half for the Indians, allowing one run on two hits in six innings in a 4-2 win over Toronto. Salazar was optioned to Triple-A Columbus after that spot start, but it's clear he's one of the Indians' five best starters.
Detroit Tigers -- OF Avisail Garcia
Garcia was up earlier in the season and he is expected to be back before September. Don't rule him out for the postseason roster. Left fielder Nick Castellanos, though not on the 40-man roster, is expected to make his major-league debut at some point because he'll challenge for a spot next spring.
Houston Astros -- OF George Springer, 1B Jonathan Singleton and RHP Jarred Cosart
Springer, Singleton and Cosart top the list of minor-league prospects who could be everyday options by September. While shortstop Jonathan Villar and a host of Triple-A Oklahoma City athletes have some potential, Springer and Cosart would offer the most immediate help. The latter threw a two-hitter in eight-plus innings on July 12 during his major-league debut at Tampa. He can hit 97 on the radar gun and has the mental edge to go with the speed.
Kansas City Royals -- Yordana "Ace" Ventura
Ventura was in the Futures Game for the second straight year. His fastball sits in the upper 90s and has been clocked as high as 102. He has struck out 36 in 34 2/3 innings since being called up to Triple-A Omaha, but his 17 walks are the concern.
Los Angeles Angels -- 1B C.J. Cron
The Angels do not have any top prospects at Triple-A Salt Lake City who have not already made an appearance in the majors. Slugging first baseman C.J. Cron, who was invited to the Futures Game, stands as the most intriguing potential call-up. Cron, who hit .287 with eight homers at Double-A, doesn't have a position to play in the majors, but he could get a shot to do some pinch-hitting when rosters expand.
Minnesota Twins -- 3B Miguel Sano
Sano, 20, is the Twins' highest-ranked prospect. With the team's season going south, Sano could be heading north to the Twin Cities this season. A power-hitting third baseman, the Twins could use his bat with Josh Willingham on the disabled list.
New York Yankees -- TBD
Thanks to their myriad injuries, the Yankees have already used virtually every healthy player on their 40-man roster this season -- pitchers Vidal Nuno, Dellin Betances and Brett Marshall, infielders David Adams and Corbin Joseph and outfielders Melky Mesa and Thomas Neal have solid chances at call-ups, though the team's top prospects such as Gary Sanchez, Tyler Austin and Slade Heathcott will likely have to wait another year.
Oakland Athletics -- OF Michael Choice
Top prospects Grant Green -- platooning at second base -- and Sonny Gray, a starter in the minors turned temporary reliever with the A's, are already on the scene. Choice, batting .292 with 11 homers and 60 RBIs at Sacramento, could be a September call-up, as could infielder Hiro Nakajima, who had been signed to be Oakland's starting shortstop last winter but who didn't make an impact initially.
Seattle Mariners -- SP James Paxton
The top hitting prospects were all brought up before the All-Star break, so the focus now is on when Seattle's so-called "big three" pitching prospects will break through. Paxton, due less to what he's done at Triple-A Tacoma and more to other factors concerning fellow up-and-comers Taijuan Walker (20 years old; Mariners are hoping to be patient with him) and Danny Hultzen (currently shut down for the second time in 2013 with shoulder stiffness).
Tampa Bay Rays -- SP Jake Odorizzi
Early-season injuries forced the Rays to tap into their pitching depth, as they called up their top four advanced pitching prospects. Chris Archer and Alex Torres are still in the big leagues and Alex Colome is on the Triple-A disabled list, but Odorizzi is still pitching in Durham and will be called up if needed.
Texas Rangers -- OF Engel Beltre, 3B Mike Olt
The Rangers called up just about every advanced level prospect they have, but Beltre, who had a brief cameo over the last two weeks of the first half and handled himself well, and Olt, who was bothered by vision problems early in the season after a poor spring training, are on the fast track. Then again, it's entirely possible neither player will be around if the Rangers need to use them to consummate a trade to strengthen the major league club.
Toronto Blue Jays -- OF Kevin Pillar
Pillar batted .348 with four homers, 15 RBIs and a 1.009 OPS in his first 24 games with Triple-A Buffalo after hitting .313 with five homers, 30 RBIs and a .802 OPS in 71 games at Double-A New Hampshire. At New Hampshire, right-hander Marcus Stroman was 5-2, 3.26 ERA after 10 starts and left-hander Sean Nolin was 5-2, 2.38 ERA, after 11 starts. Nolin has one major-league start this year.