The first thing anybody learns about Andrelton Simmons is that he doesn’t lack confidence. When somebody’s Twitter bio reads, “I am that guy that says he can do everything, but that’s just because I can,” a number of things probably roll through your mind, but none come remotely close to, “I’m worried that this kid might have self-esteem issues.”

But that’s OK. Because this team’s expectation of smashball notwithstanding, how this Braves season unfolds may hinge significantly on how the 23-year-old endures the pressure of hitting at the top of the order.

Until Monday’s season opener against Philadelphia, Simmons didn’t have a plate appearance as a leadoff hitter in the majors. He had four in the win over the Phillies (doubling and scoring a run in the third inning). If his season goes well, he will have about 700 more.

Nobody seems to be nervous about this right now, least of all Simmons, which surprises nobody.

Greg Walker, the hitting coach, said, “Fear does not seem to be a part of his game.”

Chipper Jones, whose final season overlapped with Simmons’ first, said, “He’s not fazed by anything.”

The last time Simmons felt nervous about anything? When asked the question, Simmons had to think for a moment, then said, “I guess I was a little scared before my first game. I never saw that many people in a stadium before. But after the first ground ball, it was like, ‘OK, I did this before. So no big deal.”

Right. A ground ball. What else could possibly happen?

The Braves can only hope there is strength in naivete. Simmons is the leadoff hitter by default, and there is no safety net. (Jason Heyward? B.J. Upton?) This is a lineup loaded with three-through-eight hitters, without a single prototype No. 1 or No. 2.

If the Braves were a restaurant, they would be a steakhouse that didn’t serve appetizers or salads. All meat, all the time.

The opener had pyrotechnics. Seven runs. Three homers. Be sure to come out for souvenir Caveman Club Night! It almost went unnoticed that the lineup also registered eight strikeouts. The analytics didn’t lie. The Braves are who we thought they were.

There will be an alternate universe this season. Freddie Freeman, Justin and B.J. Upton, Jason Heyward, Dan Uggla — they won’t make the baseball scream in agony every night. There will be games — games with division and postseason ramifications — when this offense will need to manufacture runs with smallball. That’s where the leadoff hitter comes in.

Simmons hit leadoff and second in the minors, so he’s not devoid of experience. But by his own admission, “I’m a more aggressive guy. I don’t take that many pitches. But early in the season I won’t be as aggressive as I normally am. I’ll adjust my game as we go. But I’m not going to make it a big deal or make it more than what it is.”

Jones said of Simmons, “Just looking at him from the side, his swing is a hair long right now. He’s not a prototypical leadoff hitter, but on this team, in this offense, he’s the option you have. He’d be better suited at two, seven or eight, but you can’t argue with what he’s done.”

He hit .289 in 49 games as a rookie, with eight doubles, two triples and three homers. He left spring training after only two games to play for the Netherlands in the World Baseball Classic — halfway around the globe, in Taiwan and Japan. When he returned to Florida, he eased concerns about the long travel by hitting .292 in eight spring games.

“We’re going to monitor his situation,” Walker said. “The red flag would be if he starts pressing, but he’s never done that before. Last year in the playoffs, the first time he was up he got a base hit. I don’t doubt the kid a whole lot. Until he gives me a reason to, I’m not going to doubt him.”

Walker has watched Simmons make adjustments in the batting cage. He shows a maturity and baseball intelligence rare for his age. “We trust his baseball knowledge,” Walker said.

Jones speculated that Simmons probably has been playing baseball since he was 4 years old in Curacao. Close.

“I think (3 years old),” Simmons said. “My first memory is being in the backyard with a glove.”

Twenty years later, nobody doubts his glove. If the offense doesn’t follow, the Braves will need to figure out a Plan B, but so far they have no reason to doubt a guy who says he can do everything.