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Even though a majority of the game's top prospects have already received promotions, teams will receive an infusion of fresh, young talent on Sept. 1 when the active roster expands from 25 to 40 players.

With roughly five weeks remaining in the regular season, expanding rosters will allow teams to address their needs at the major league level by essentially plucking specific talent from within their farm systems. In general, it's an opportunity for every organization to add bench and bullpen depth by utilizing its full 40-man roster.

In anticipation of what should be a flurry of promotions starting next Monday, we've got you covered with a look at the top prospects ticketed for the major leagues for the season's final month. The rankings for this article are based primarily on Prospect Pipeline's midseason top 50 update, though factors such as 2014 performances, 40-man roster status and teams' specific needs at the major league level were also considered.

Here are the top 25 prospects most likely to be called up on Sept. 1.

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The 2013 playoff races were defined by strong rookie performances.

There was Michael Wacha, who went from first-round draft pick in 2012 to No. 2 starter for the St. Louis Cardinals down the stretch and well into the postseason. Gerrit Cole and Sonny Gray had similar impacts on their respective teams, as both right-handers reached the major leagues in the middle of the season and ultimately shined in their first tastes of playoff baseball.

Meanwhile, Billy Hamilton literally stole the show on the other side of the ball. The infamous speedster was called up in September and blew past all reasonable expectations by batting .368 with nine runs and 13 stolen bases over 13 games.

This season, there should be just as many, if not more, big-name prospects who influence their team’s quest for a playoff berth.

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The Los Angeles Angels suffered a potentially crushing blow Wednesday night when they lost ace Garrett Richards for the next six to nine months with a torn patellar tendon in his left knee.

Richards' injury couldn't have come at a worse time for the Angels, who currently hold a two-game lead over the Oakland A's in the American League West with an MLB-best 76-50 overall record. With the right-hander sidelined for the rest of the season, the Angels' rotation suddenly is much less threatening, especially in the context of a five- or seven-game playoff series.

However, rookie Matt Shoemaker did his best to ease those concerns Thursday night, guiding the Angels to a 2-0 victory and four-game road sweep of the Boston Red Sox.

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The 2014 season has seen a number of notable prospects receive call-ups to the major leagues. Even with the final month approaching, there will be more to come—and soon.

September brings with it expansion to 40-man rosters. Only a little more than a week away, that should allow for plenty of promotions of prime prospects.

Highly regarded youngsters like Marcus Stroman, Jonathan Singleton, Gregory Polanco, Ken Giles and Javier Baez have been seeing regular time for their respective clubs for quite some time now. Others, like Oscar Taveras and Taijuan Walker, have been shuttling up and down between the minors and majors for much of the year.

Earlier this week, the Boston Red Sox recalled outfielder Mookie Betts for yet another stint. He should stick for longer this time, considering they demoted incumbent center fielder Jackie Bradley Jr. to Triple-A Pawtucket to free up playing time for Betts.

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The expansion of the active roster from 25 to 40 players on September 1 means something different to every team. 

For clubs hoping to retain a lead in the standings or make one last run at the postseason, it’s essentially an opportunity to address deficiencies by handpicking the top talent from within the organization. 

Meanwhile, teams that have already thrown in the towel for the season have the freedom to experiment with their lineups and audition younger players.

In both scenarios, the common denominator is the use of prospects over the final month of the season. Whether those call-ups are fueling a team toward the postseason or competing for a spot in next year’s starting lineup, the success of prospects in September can receive as much attention as the playoff and MVP races.

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We’re now approaching the end of the minor league season, but there are plenty of prospects who continue to open eyes with their performances across the rookie, short-season and full-season levels.

For most players the season will conclude at the end of August, with a league playoff title representing the ultimate goal. However, there also will be several notable prospects, many of whom are featured in this article, whose seasons are extended with a September call-up.  

As we did in the series’ previous installments, this week’s list of players once again combines reports on both hitters and pitchers in the same slideshow. However, we’ll only be looking at just the hottest players because, well, there are a lot of them with the season winding down, and they’re all worth mentioning.

Here are the hottest players at every minor league level.

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One could say that 2014 first-round draft pick Casey Gillaspie was born to play baseball.

The Tampa Bay Rays selected Gillaspie out of Wichita State with the No. 20 overall pick this past June, targeting the switch-hitter’s advanced approach and big-time power. Plus, it certainly didn’t hurt that he also came from a baseball family.

Gillaspie’s father, Mark, was an All-American outfielder at Mississippi State before spending eight years in the minor leagues, reaching the Triple-A level with two different teams before hanging up his spikes after the 1988 season.

Though he never played in the major leagues, Mark still had a solid eight-year career, batting .287/.421/.503 with 138 home runs, 604 RBI and more walks (692) than strikeouts (676) in 880 games.

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Twitter erupted Saturday night following news that Kris Bryant was pulled during the middle of Triple-A Iowa’s game. He didn’t appear to suffer an injury in the game, which only fueled speculation that the 22-year-old slugger was headed for The Show.

Unfortunately, it was learned soon thereafter that Bryant departed the game after aggravating a left-foot injury suffered earlier in the week, when he fouled a ball of his big toe, and would undergo an MRI the following day.

And just like that, the excitement regarding Bryant’s potential call-up shifted to concern about the injury. With less than a month left in the minor league regular season, any injury requiring a trip to the disabled list would likely kill his chances of receiving a September promotion.

Thankfully, the MRI revealed no structural damage to Bryant’s foot. The Cubs’ top prospect returned to the lineup Tuesday.

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With rosters set to expand from 25 to 40 players on Sept. 1, it's only a matter of time until there's an influx of fresh, young players arriving in the major leagues.

We previously looked at the call-up odds for baseball's top-ranked prospects as well as those prospects considered to be long shots for a promotion next month.

Today, however, we'll be breaking down another batch of prospects who could be in the major leagues by the end of the year, provided they turn strong finishes to the minor league season at their respective levels.

With that being said, here are seven prospects making a late push for a September call-up based on their performance so far this season.

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Apparently 10 is the magic number for Corey Kluber.

The Cleveland Indians ace was brilliant on Friday night against the Baltimore Orioles, allowing one run on five hits and two walks while striking out 10 batters over 7.2 innings.

The outing marked Kluber’s second 10-strikeout performance in the past week, and he’s now fanned exactly 10 batters in four of his last six starts. Overall, it was Kluber’s eighth start this season with double-digit strikeouts.

Kluber, 28, has been nothing short of dominant since the All-Star break, pacing all starting pitchers with a 0.76 ERA, 0.69 WHIP and 55 strikeouts over 47.2 innings. On top of that, the right-hander has allowed just 27 hits, none of which have left the park, and six walks during that span.