Dodgers will learn that October can be magical — or mortifying

ATLANTA — The Dodgers will begin the 2013 playoffs against the Atlanta Braves here Thursday, but their most difficult postseason opponent has already shown up.

It came swaggering into their clubhouse bearing sordid histories and fresh doubts. It came in with a bold and powerful relentlessness that gave even baseball’s most cocksure and carefree team pause.

Its name is October.

The Dodgers have shown they can reasonably handle any nine players put in front of them, but can they handle October?

QUIZ: Postseason Dodgers -- what do you know?

History offers no consistent proof. The resumes of their starters and best players offer no strong evidence. They became the best team in baseball in the lazy haze of late June and July, and they clinched the National League West Division title during the weary days of September, but few of them have any idea about success in October.

The stage is different now. After 162 games of intermittent pressure, every play means something. Every pitch is examined from all angles, every swing is dissected by a dozen experts, and every manager’s decision is put under a national microscope.

The previous five months can shape lives and provide paychecks, but October creates legacies and defines careers.

“It’s big,” said Nick Punto. “It’s why you play the game.”

It’s so big, in the past year Dodgers General Manager Ned Colletti has acquired such players as Punto, Skip Schumaker and Michael Young — they have played in a combined 77 postseason games — expressly for October.

But those guys are neither the team’s leaders nor its stars, which are mostly empty of postseason juice. One could argue that with the start of October, the most important Dodgers are also the most vulnerable.

Their manager, Don Mattingly, has never managed a postseason game. How will he handle the heat? He sometimes struggled with the sort of late-inning game maneuvers that October will push to the headlines. The Dodgers have yet to renew his contract for next season. Surely he won’t have to win at least one round to keep his job.

Or will he?

“I think you feel pressure all the time for your club to perform and that you’re prepared,” Mattingly said Wednesday before the team’s workout at Turner Field. “But just like I’ll ask my players to do, I’m going to try to … make sure you cut all the surrounding circumstances away as much as possible and manage a baseball game.”

The Dodgers’ series-opening starter, Clayton Kershaw, has a 5.87 earned-run average in five postseason appearances. The last time he was a Game 1 pitcher, he opened the 2009 National League Championship Series at home against the Philadelphia Phillies by allowing five runs in 4 2/3 innings in an 8-6 loss.

The regular-season domination by Kershaw reminds some of Orel Hershiser in 1988, when he won the Cy Young Award while setting a record with 59 consecutive scoreless innings. Yet Hershiser didn’t really cement his bulldog legacy until October of that season, when he went 3-0 with a 1.07 ERA in five postseason starts and one rather memorable relief appearance.

“When I look at guys … I always love watching Andy Pettitte and his postseason success,” Kershaw said Wednesday of the New York Yankees left-hander with 19 postseason victories. “That’s stuff that you remember … it definitely is fair, I would say, for a legacy.”

The Dodgers’ No. 2 starter, Zack Greinke has a 6.48 ERA in three postseason appearances. The Dodgers Nos. 3 and 4 starters, Hyun-Jin Ryu and Ricky Nolasco, have never pitched in the postseason.

The Dodgers’ veteran left fielder, Carl Crawford, batted .143 in his last division series in 2010 with the Tampa Bay Rays, and is hitting just .253 in 21 postseason games. The Dodgers’ most valuable player, Hanley Ramirez, has never appeared in a postseason game, and neither has leadoff hitter Yasiel Puig nor closer Kenley Jansen.

Even the one Dodgers star who had some postseason success also struggled at the same time. Adrian Gonzalez batted .357 for the San Diego Padres in his only postseason experience in the 2006 division series against the St. Louis Cardinals. Yet he didn’t have an extra base hit, didn’t drive in a run, and the Padres lost in four games.

“You are curious to see even people with strong resumes, in the postseason, how they do,” said Colletti. “People’s careers are accentuated on what they do in the month of October.”

October could make legitimate stars out of the Dodgers novices. October could also confirm the October toughness of those role players, including relievers Brian Wilson and J.P Howell, who have a combined 33 strikeouts and eight walks in 23 postseason appearances.

But sometimes October wins. And when it does, careers can lose.

Surely you remember Jonathan Broxton? In 2008 and 2009, the Dodgers reliever saved a combined 50 games. But both years, he lost NLCS battles with Matt Stairs that led to Philadelphia Phillies victories, and he was never fully welcomed at Chavez Ravine again.

“You know, I think we all want to know what guys will do in big situations,” said Mattingly.

October is so big, some of this year’s playoff teams are trying to own it with a spiffy nickname. The Pittsburgh Pirates are calling it Buctober. The Braves are claiming it’s Choptober.

The Dodgers, for now, will have to settle for Questionmarktober.

bill.plaschke@latimes.com

Twitter: @billplaschke