5 Biggest MLB Storylines To Watch This September

One of the greatest times of year is upon us.  As the evenings grow colder and shorter, it's a sure indication that MLB's pennant chases are in full swing. 

This year's cast of characters contains mostly familiar faces, with a few newcomers.  If the season ended today, the New York Yankees, Boston Red Sox, Texas Rangers, Philadelphia Phillies, Milwaukee Brewers and Atlanta Braves would be in the postseason and right where we thought they would be.  The Detroit Tigers would be in as a minor surprise, and the Arizona Diamondbacks as a major surprise.

Things are close this year, as three of the division races are within four games, and another two are within 6.5 games with just over a month to play.  The Chicago White Sox, Cleveland Indians, Los Angeles Angels and San Francisco Giants all have life and won't go away quietly.

Additionally, there are numerous individual achievements on the line this season. 

The Tigers' Justin Verlander is in the midst of the best season for a starter in at least a decade, Adrian Gonzalez has been an incredible offseason acquisition for the Red Sox, as they battle the surprising Curtis Granderson and the Yankees for the AL East crown and rookie phenom Craig Kimbrel of the Braves is due to shatter the rookie saves record.

Here are five of the best storylines to follow in September.

Yankees vs. Red Sox

The ultimate rivalry is enjoying one of its best seasons ever, as the two most dominant teams in the AL have been neck and neck for nearly the entire season.

Curtis Granderson and Adrian Gonzalez are firmly in the AL MVP discussion, and the division is completely up for grabs.  Both teams will make the playoffs, but it will be a classic battle between baseball's biggest rivals for the division crown.

The fun kicks off tonight as the Yankees head to Boston for a three-game set—the first of six remaining games between the two teams.

Craig Kimbrel's Amazing Season Concludes

Quietly, Craig Kimbrel is enjoying a dominant season as the Braves closer.  The fact that he's a rookie (well, technically at least) is all the more amazing.

He's 40-of-45 in save opportunities with a 1.70 ERA and a 1.01 WHIP, and he has stabilized the Atlanta Braves bullpen.

With a month left in the season, Kimbrel has already tied Neftali Feliz's year-old rookie saves record.  He's a lock for the NL Rookie of the Year and could be in the midst of concluding one of the best rookie seasons in the history of baseball.

Can the Diamondbacks Hold Off the Defending Champs?

As both the Pittsburgh Pirates and Cleveland Indians have slumped, the Arizona Diamondbacks have emerged as baseball's biggest surprise.

The D-Backs wiped out a six-game losing streak by winning their next six games and have the defending champion Giants on the ropes.

Carried by excellent seasons from Ian Kennedy and Justin Upton, the Diamondbacks still have six games left with the champs so anything is possible.  It is a great storyline to watch in a division that gets overlooked.

How Good Is Justin Verlander?

Justin Verlander has single-handedly carried the Detroit Tigers pitching staff.  They're leading the AL Central by five games but are one game under .500 in those Verlander doesn't pitch.

He has already become the first pitcher in nearly a decade to win 20 games before September, and it will be interesting to see how many wins he ends up with.

Besides wins, he leads the majors in strikeouts and WHIP and is third in ERA.  He's running away with the AL Cy Young Award and warrants serious MVP consideration.

Can the Brewers Challenge the Phillies for the NL Title?

While the Philadelphia Phillies are still the team to beat in the NL, the Milwaukee Brewers are finally playing like the team everyone thought they should be.

The Brewers have gone an astounding 32-11 in the second half to run away with the NL Central and are starting to challenge the Phillies for the best record in the NL.

With a loaded lineup led by Ryan Braun and Prince Fielder, and starters Yovani Gallardo, Randy Wolf, Shaun Marcum and Zack Greinke, the Brewers appear to be the team most likely to challenge the Phillies pitching triumvirate as the NL's World Series representative.