October baseball has a way of chewing up players and spitting them out. The big stage and high stakes can push postseason newbies to try too hard, motivating them to end every game with one vicious swing. Every well-intentioned player insists they won’t let the pressure affect them. But it’s human nature. It happens.

In the biggest games of the season, however, Anthony Rendon has maintained his carefree, tranquil demeanor. While the rest of the Nationals’ offense struggled in the first two games of the National League Division Series against the San Francisco Giants’ stout pitching, Rendon’s play has been the same as the regular season when he was the Nationals’ most valuable position player. The 24-year-old’s sweet swing and vacuum-cleaner glove have not slumped.

“He’s been the same old guy we’ve seen for the last six months,” Manager Matt Williams said. “It started on opening day and has not subsided yet. He’s patient. He understands what he does well. He works at-bats and works counts. . . . You look at him and go, ‘He looks like a 30-year-old that’s been in the league for six or seven years.’ We continue to forget how young he really is.”

Facing a 2-1 deficit in the best-of-five series, the Nationals need another win in Game 4 late on Tuesday night to keep their season alive. Their pitching has been stellar, a few mistakes magnified by the pressing offense. Including a 4-1 victory in Game 3 on Monday, the Nationals have scored seven runs in 36 innings. The team is hitting an abysmal .172 (22 for 128) with 33 strikeouts and nine walks. Without Rendon’s 7-for-15 postseason, the Nationals would be hitting .133.

“It’s still a game,” Rendon said after an 18-inning Game 2 loss in which he finished 4 for 7 but the rest of the Nationals went 5 for 55.

Without Rendon, the Nationals’ offense would be nearly non-existent. He and Asdrubal Cabrera have the only Nationals’ hits with runners in scoring position. Bryce Harper is hitting .214 (3 for 14) but has provided two crucial solo home runs and a key walk during the Nationals’ seventh-inning rally in Game 3. Cabrera is hitting .250 (3 for 12) but also smacked a key solo home run in Game 1 and an RBI single in the seventh inning of Game 3.

Rendon is “a good player, great player,” Giants Manager Bruce Bochy said. “Solid all around. A tough out. A very good third baseman and runs well. This guy is a real nice player. He can probably play anywhere in the infield, too. I think Washington has a guy they’re going to keep for a long time there.”

If the Nationals hope to advance to the National League Championship Series, they will need more production from the rest of their lineup. Denard Span snapped an 0-for-11 skid with a 2-for-4 performance in Game 3. Jayson Werth, one of the best postseason hitters in baseball, has hit the ball hard but is 1 for 14 and two walks. Ian Desmond is 2 for 14 with five strikeouts. Adam LaRoche and Wilson Ramos, who had an important bunt in Game 3, are a combined 2 for 27.

Rendon, who shuns attention, has played each game with ease and comfort. He once yawned during a regular season at-bat and looks like he could do the same in the playoffs. While teammates beat Giants Game 2 starter Tim Hudson’s sinker into the ground, he took controlled swings and went 4 for 4. In Game 3, against the Giants’ best starter, Madison Bumgarner, Rendon smacked two hits. If Rendon has been nervous, he has hidden it well and hasn’t allowed it to affect his play.

“I’ve always been calm, as long as I can remember,” Rendon said late in the season. “I’m trying to see, in high school or college, I’ve never been like, ‘Rah! Rah!’ kind of guy. It’s always been just, ‘All right.’ I always feel happy for my teammates, but I’m not going to be the one at the top of the dugout yelling.”

In his first full major league season, Rendon was an all-around offensive force. He hit .287/.351/.473 with 21 home runs and 83 RBI. He scored 111 runs, the most in the NL. His strong defense and ability to play second and third base solidified the Nationals infield when Ryan Zimmerman suffered two injuries. Because of his hitting, defense and base running, Rendon was worth 6.6 WAR (Wins Above Replacement), according to FanGraphs.com, tied for the third-highest mark in the majors behind Mike Trout and Andrew McCutchen.

“He just doesn’t get flustered,” LaRoche said late in the season. “He’s the same guy whether he’s 8 for 10 or 0 for 15. A lot of guys will start changing their swing, their approach, their philosophy. He just really has a knack of getting there after he loses it for a couple games. He can get back there really quick.”

Adam Kilgore and Rick Maese contributed.