Credentials: 98-64, NL East champions
Last postseason appearance: 1981, lost to Dodgers 3-2 in NLCS
Best postseason finish: NLCS (1981)
Manager: Davey Johnson (23-23 postseason record)
Player to watch: SS Ian Desmond
Pitcher to watch: LHP Gio Gonzalez
The skinny: The Nats have been consistent from Opening Day, posting a winning record each month and holding at least a share of the NL East lead for all but 10 days in a six-month season. Desmond is but one standout in a potent lineup also highlighted by Bryce Harper, a resurgent Jayson Werth, MVP candidate Adam LaRoche and veteran Ryan Zimmerman, but it's the arms that make the difference. Even without Stephen Strasburg, the Nats' rotation should be formidable in October.
Credentials: 97-65, NL Central champions
Last postseason appearance: 2010, lost 3-0 to Phillies in NLDS
Best postseason finish: World Series champions (1919, 1940, 1975, 1976, 1990)
Manager: Dusty Baker (18-21 postseason record)
Player to watch: 1B Joey Votto
Pitcher to watch: RHP Johnny Cueto
The skinny: Division champs for the second time in three years, the Reds will start with trying to win a postseason game this time after being swept by the Phillies in the 2010 Division Series. Baker has been sidelined with health problems but is back for the playoffs to lead Votto, Brandon Phillips, Jay Bruce and the rest of the Redlegs. Cy Young candidate Johnny Cueto leads a rotation deep enough that the fourth starter, Homer Bailey, pitched a no-hitter last week. And don't forget the dominant Aroldis Chapman throwing 100-plus mph to finish games.
SAN FRANCISCO GIANTS
Credentials: 94-68, NL West champions
Last postseason appearance: 2010, beat Rangers 4-1 in World Series
Best postseason finish: World Series champions (1905, 1921, 1922, 1933, 1954, 2010)
Manager: Bruce Bochy (12-15 postseason record)
Player to watch: C Buster Posey
Pitcher to watch: RHP Matt Cain
The skinny: The Giants have plenty of new faces since winning it all in 2010, but Posey remains the key. His return after missing most of last season with an injury has sparked an offense that gets it done mostly in drips and drabs (only Posey, with 24, has more than 12 homers). Cain sets the tone for the pitching staff, and he, lefty Madison Bumgarner and Pirates castoff Ryan Vogelsong have compensated for Tim Lincecum's decline. Sergio Romo and Santiago Casilla have shared closer duties this year, with Romo getting the call lately.
Credentials: 94-68, NL wild card
Last postseason appearance: 2010, lost 3-1 to Giants in NLDS
Best postseason finish: World Series champions (1914, 1957, 1995)
Manager: Fredi Gonzalez (no postseason appearances)
Player to watch: 3B Chipper Jones
Pitcher to watch: RHP Kris Medlen
The skinny: Shaking off last September's collapse, the Braves earned a wild-card matchup against the team that kept them home for last October, the Cardinals. Jones has been a surprise standout along the way, proving he still has plenty to offer even in the midst of his farewell tour around the majors. Medlen has been a revelation since moving to the rotation, as the Braves have won 23 consecutive games he has started heading into Friday's game. And once any of Atlanta's starters gives the ball to closer Craig Kimbrel, it's usually game-over for the opposition.
ST. LOUIS CARDINALS
Credentials: 88-74, NL wild card
Last postseason appearance: 2011, beat Rangers 4-3 in World Series
Best postseason finish: World Series champions (11 times, most recently in 2011)
Manager: Mike Matheny (no postseason appearances)
Player to watch: LF Matt Holliday
Pitcher to watch: RHP Kyle Lohse
The skinny: The defending champs were the last team to secure a playoff berth, but they're in the tournament. Pitching leads the way for the post-Pujols Cards, with everyone in the rotation sporting a sub-4.00 ERA and the shutdown duo of Mitchell Boggs and Jason Motte anchoring the bullpen. Holliday and Carlos Beltran lead an experienced lineup that has gotten the job done for rookie manager Matheny as the former catcher has stepped in for the retired Tony La Russa.