Pennant races in both leagues are heating up with just over 15 games remaining. Here's what's happening in Major League Baseball:

National League Report: Braves Sweep Nationals; Cardinals Split With Dodgers

The Washington Nationals (89-57) still have the best record in baseball, but their NL East lead is down to 5.5 games after being swept by the Atlanta Braves (84-63) over the weekend. The Braves' 5-1 victory over Washington in Sunday's finale gave them an eight-game lead in the NL Wild Card. Since Washington has shut down starter Stephen Strasburg to protect him from overuse just a year removed from arm surgery, the Nationals have to find other players who can step up in his absence.

The St. Louis Cardinals (77-70) needed a 12th-inning rally to get a 5-2 win over the Los Angeles Dodgers (76-71) and gain a split of the teams' weekend series in L.A. The Dodgers are just one game behind the Cardinals for the second NL Wild Card spot. The resurgent Milwaukee Brewers are just 2.5 games back with the fading Pittsburgh Pirates now three games out. The Cincinnati Reds (88-59) and San Francisco Giants (83-63) each are comfortably ahead in their divisions, with 11 and 7.5 game leads respectively.

American League Report: Yankees Beat Rays; White Sox Sweep Twins

Tied with Baltimore for the AL East lead heading into the weekend, the New York Yankees (83-63) won two of three games from Tampa Bay (78-68), while the Orioles (82-64) dropped two of three to the Oakland Athletics (84-62). The first-place Yankees' schedule gets much easier with 13 of their final 16 games against teams with losing records.

After sweeping a three-game series from the Minnesota Twins this weekend, the Chicago White Sox (79-66) now lead the AL Central by two games over Detroit (77-68). The teams have a make-up game set for Monday in Chicago. The Texas Rangers (87-59) still have the AL's best record, but their lead over Oakland is down to just three games. The Athletics and the Orioles still hold the two AL Wild Card spots, with the Los Angeles Angels just 2.5 games out.

Play of the Week: Jason Heyward, Atlanta Braves

As his team closes in on a playoff spot, Atlanta Braves' outfielder Jason Heyward is trying to help their chances any way he can. In the video below, Heyward makes a leaping catch to keep Milwaukee's Ryan Braun from getting an extra-base hit.

Upcoming Series To Watch: Texas Rangers at Los Angeles Angels

The Texas Rangers (87-59) have been at the top of the American League West standings for most of the 2012 season. In this three-game series starting Tuesday, the Rangers can take a huge step toward clinching the division title and keeping one of their fiercest rivals out of the post-season. Los Angeles (80-67) is 7.5 games behind the Rangers in the AL West, but just 2.5 games in back of Baltimore for the second AL Wild Card spot. The Angels need to win this series to keep pace in both races.

Fantasy Player to Add: Darwin Barney, Chicago Cubs

After putting up mediocre numbers for much of the year, Cubs' second baseman Darwin Barney has put together an 11-game hitting streak in September to raise his batting average five points. While Barney won't deliver huge power numbers, he will have a chance to help your team add runs and average.

Fantasy Player To Drop: Danny Espinosa, Washington Nationals

Though he's had a solid season with 16 home runs, 19 steals and a .722 OPS, Nationals second baseman Danny Espinosa is currently struggling at the plate. Espinosa is 1-for-21 over his last six games, including nine strikeouts in his last 11 at-bats. It's time to sit him so he doesn't do any more damage.

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