Although it was just the beginning of what will likely be several waves of players finding their ways to the majors as September call-ups, a few big names were given their ticket to the big leagues on September 1.
The roster expansions will not truly be completed until after the minor league playoffs have completed, and there is nothing holding the parent club back from bringing up their top MLB-ready prospects.
Here's my list of the top-25 players that got call-ups on the first day of September.
The 26 year-old starting pitcher earned his call-up following a 8-9 season in Triple-A.
Brandon Dickson posted a 3.95 ERA and a 7.1 K/9 ratio while working his way up to the Majors and into the St. Louis Cardinals bullpen.
He will try to demonstrate that he deserves an audition in spring training to attempt to crack their starting rotation in 2012.
The Baltimore Orioles promoted Kyle Hudson, a speedy outfielder, as the rosters expanded.
Hudson batted .296/.375/.336 in Triple-A for the Orioles and added 26 stolen bases to his stat-line.
Hudson was the Orioles fourth round draft pick in 2008.
Andrew Romine, the fifth round pick of the Angels in the 2007 draft, was called up for his second stint with the Angels as rosters expanded.
The 25-year-old shortstop was batting .281/.363/.346 with four homers and 35 RBI for the Angels Triple-A club.
Russell Mitchell put up some decent power numbers in Triple-A to earn his promotion.
The 26-year-old third baseman was batting .283/.372/.503 with 16 homers and 69 RBI in Triple-A.
Mitchell was originally a 15th round draft pick of the Dodgers in the 2003 draft.
Nick Hagadone was previously rated the No. 44 prospect in baseball prior to the 2010 season.
Although his stock may have dropped slightly, he still pitched well enough in relief this season to earn his promotion.
Hagadone 6-4 with a 2.79 ERA in 46 minor league appearances this season. He added a 9.8 K/9 ratio to his stat-line to work his way up to the Majors.
Andy Dirks, the Tigers eighth round draft pick in 2008, earned his promotion based on a strong season at Triple-A with his bat.
The 25-year-old outfielder batted .325/.368/.522 with seven homers and 24 RBI this season.
Despite picking up eight losses, Anthony Vavaro pitched well enough to earn his way back to the Braves Major League roster.
The 26-year-old reliever also earned two wins in his 38 appearances in Triple-A, posting a 2.90 ERA and a 10.5 K/9 ratio this season.
The promotion marks his second stint with the Braves this season.
Jeremy Horst did his part in Triple-A this season, silencing enough bats to catch the Reds attention.
The 25-year-old lefty posted an impressive 2.81 ERA in 36 appearances out of the bullpen.
He'll join the Reds bullpen and begin auditioning for a role in the majors in 2012.
Logan Schafer made stops at every level of the minors this season before finally being promoted to the Brewers.
The 24-year-old outfielder had a combined batting line of .315/.385/.439 with five homers and 43 RBI.
He will be used primarily off the bench in a pinch-hit role, but he should see some at-bats this September.
Martin Maldonado earned a call-up and should see some playing time this September as the Brewers get ready for the postseason and try to give a little extra rest to their primary catchers.
Maldonado, 25 years old, had a good season in Triple-A leading up to this promotion.
For 2011, he batted .321/.410/.537 with eight homers and 25 RBI in his time at Triple-A.
At 27 years old, Shawn Kelley may not be able to be called a prospect anymore, but he put up some dominating numbers in Triple-A in 2011 leading to his promotion.
In 12 Triple-A appearances, Kelley posted a 1.84 ERA with a 9.2 K/9 ratio.
He will join the Mariners bullpen for the remainder of the season and begin auditioning for a major league job in 2012.
Brandon Guyer's promotion gives the Rays another productive bat off the bench in the outfield for the remainder of the season.
Guyer, 25 years old, put together an impressive .312/.384/.521 batting line with 14 homers and 61 RBI this season.
With B.J. Upton reportedly on the trading block, Guyer could find a spot with the Rays next season in the big leagues in a corner outfield position (with Desmond Jennings moving to center field).
Welcome back to the majors, Juan Francisco!
The 24-year-old third baseman has been up and down with the Reds a few times over the past two seasons, but he should stick with them the remainder of this season.
He earned his most recent promotion based on the strength of his Triple-A season.
He posted a batting line of ..307/.334/.540 with 15 homers and 50 RBI.
The Diamondbacks added some bullpen depth as they try to return to the playoffs by promoting Ryan Cook as one of their first September call-ups this season.
Cook, 24 years old, posted a 2.12 ERA and 6.4 K/9 ratio in 14 Triple-A appearances this season.
He will audition for a spot on the 2012 roster as he helps the Diamondbacks oust the 2010 World Series Champion San Francisco Giants from postseason contention.
Josh Satin earned his second promotion of the year to join the Mets big league club.
After starting the season in Double-A, Satin was promoted to Triple-A for the first time in his career earlier this season.
He batted .323/.411/.495 with 12 homers and 76 RBI combined between Double-A and Triple-A this season.
Efren Navarro, a 25-year-old first baseman, has joined the Los Angeles Angels as a September call-up.
Navarro had an impressive Triple-A season this year, batting .317/.368/.488 with 12 homers and 73 RBI.
Jeremy Moore is another player that has joined the Angels major league roster thanks to September roster expansion.
Moore, 24 years old, batted .298/.331/.545 with 15 homers and 66 RBI this season for Triple-A Salt Lake.
He added 21 stolen bases as well, giving the Angels a productive bat and base-path antagonist to utilize down the stretch.
Luis Marte spent the majority of the 2011 season at Double-A for the Tigers, but was still offered a September call-up to show his stuff on the Major League level.
Marte, 24 years old, had a 1.92 ERA and 11.2 K/9 rate in 25 minor league appearances in 2011.
It wasn't very surprising to see the Yankees bring Chris Dickerson back up to the Majors when rosters expanded.
Dickerson, 29 years old, was productive in his first stint with the Yankees earlier this season.
He batted .321/.367/.393 in 41 major league games.
Brandon Laird is also back in the Bronx for another stint with the Yankees.
Laird, 23 years old, batted .260/.288/.422 with 16 homers and 69 RBI in Triple-A this season.
He is good insurance down the stretch at the hot-corner in case Alex Rodriguez suffers an injury.
The Yankees also have Eric Chavez for third base, but Chavez's health has been a question mark the past few seasons, including a lengthy stint on the disabled list this year as well.
Switching away from the Yankees and over to the other side of baseball's most notorious rivalry, the Red Sox promoted Felix Doubront back to the major leagues.
Doubront, a 23-year-old lefty, went 3-5 with a 3.96 ERA and 8.6 K/9 ratio in Triple-A this season.
Doubront will likely pitch out of the bullpen for the Red Sox the remainder of the year; however, he could provide them with a spot start should the need arise.
And just like that, we're back to players returning to pinstripes (hey, I couldn't help that the Yankees were one of the most active teams on the first day of roster expansion).
Scott Proctor, re-acquired by the Yankees earlier this season from the Atlanta Braves, will make his return to the Yankees after being traded away in 2007.
Proctor, 34 years old, had been pitching in Triple-A this season, combining for a 1.50 ERA and a 12.0 K/9 ratio in 20 appearances.
He will add depth and experience to the Yankee bullpen down the stretch.
Devin Mesoraco, Baseball America's No. 64 overall rated prospect entering the season, is one of the first prospects rated in the top 100 to earn a September call-up in 2011.
Mesoraco, a 23-year-old catcher, batted .289/.371/.484 with 15 homers and 71 RBI this season in Triple-A.
Mesoraco will be given at-bats and playing time behind the plate as he prepares to take over for Ramon Hernandez behind the plate for the Reds, most likely beginning next season.
Jacob Turner is our youngest September call-up so far and one of the highest rated prospects by Baseball America.
Turner, who was rated No. 21 overall by Baseball America, is just 20 years old.
He combined for a 4-5 record and 3.44 ERA over 20 starts combined between Double-A and Triple-A.
Turner will show his stuff as he auditions for a rotation spot with the Tigers in 2012.
Jesus Montero may have been the No. 3 rated prospect by Baseball America headed into the season, but he is the most anticipated September call-up around Major League Baseball.
Montero earned his call-up following a strong season in Triple-A in which he batted .288/.348/.467 with 18 homers and 67 RBI.
The 21-year-old record has a long career to look forward to in the big leagues.