Most every Major League Baseball game is preceded by a carefully-orchestrated set of exercises that, when combined, create a rhythmic choreography that is commonly known as batting practice. (The Washington Post)

The official part of Wednesday, June 5, for the Washington Nationals began at 7:06 p.m., when right-hander Dan Haren fired a fastball to Omar Quintanilla of the New York Mets, and the game began. At 10:18 p.m., Ryan Zimmerman lined out to center field, and the game ended.

But four hours before the first pitch, before the national anthem, before the stands filled, a door in the center field wall at Nationals Park opened, groundskeepers rolled out “the cage” and the work day actually began. In that cage, the Nationals take part in a baseball tradition that dates back to the 19th century: batting practice.

A baseball season is defined by its grinding rhythm, and there is no more metronomic element than those 50 minutes when a team prepares on the field. To those who are around the game daily, it is such a part of the backdrop that it almost goes unnoticed, never mind that balls regularly whiz by heads, that players and coaches occasionally get smoked.

“There’s a lot of routine,” Nationals hitting coach Rick Eckstein said. “But there’s a lot going on.”

There is an obvious infrastructure, with screens placed in front of the pitcher, in front of first base and both in front of and behind second — to protect not only a middle infielder taking relays at the bag but a coach who hits grounders to outfielders from short center. There are characters simultaneously essential and obscure because the same person throws batting practice to the same group each day and the same relief pitchers stand in the same spots in the outfield, whether to shag balls or shoot the breeze.

And lest anyone think the relaxed, easy feel means it’s a relaxed, easy time, check out the cast leaning against the cage when the Nationals hit: Eckstein, normally on a perch directly behind the hitter; Manager Davey Johnson, a hitting instructor of some renown himself; and General Manager Mike Rizzo, who is not there for appearance’s sake.

“I watch approaches, mechanics, changes in stances, hand placement, what they’re working on,” Rizzo said. “I want to be in the know.”

The structure

When batting practice — BP in the parlance of anyone involved in the game — begins, it looks simple enough. Trent Jewett, the Nationals’ third base coach, takes his position on the small wooden ramp that serves as a makeshift mound closer to the plate. He throws to the first group of hitters — four of that night’s starters, a group anchored by shortstop Ian Desmond and center fielder Denard Span.

A basket of balls sits to Jewett’s left, an L-shaped screen in front of him. And when he throws his first pitch, the dance begins. What each team in the majors goes through looks remarkably the same. What each player is looking for over the next 50 minutes varies by the individual, his circumstances, his habits, his preferences.

“If I’m feeling good, if I’m where I want to be, I use it for nothing more than to get loose,” Nationals first baseman Adam LaRoche said. “That’s it. See pitches. When I’m not, that’s when a lot of times we get to mechanical issues.”

For a 7:05 p.m. start — the most common time for a Nationals home game — Washington’s batting practice begins at 4:50 p.m. This is after the starting pitchers have hit and after any needy Nats have come out for early work, something most of them take care of in the two cages under the stands between the dugout and the clubhouse.

According to research provided by the National Baseball Hall of Fame and Museum, the earliest signs of batting practice date from the mid-1880s, a time when, according to Peter Morris’s book “A Game of Inches,” “hitting was viewed as an instinctive skill that could not be learned or taught.” Moreover, frugal owners didn’t want to waste or damage balls that could be used in a game. The practice didn’t become structured until at least the early 1900s, when there was still debate over its effectiveness.

Now? “Days we don’t hit, I don’t feel good,” Nationals veteran Chad Tracy said.

Those days are limited mostly to early afternoon starts or when it rains. Otherwise, there is structure. Jim Lett, the team’s bullpen coach, stands on the third base side of the cage, hitting grounders across the diamond to first. Nilson Robledo, one of the team’s bullpen catchers and batting practice pitchers, smacks fungoes from the first base side of the cage to Zimmerman and Tracy at third. “There’s an art to it,” said bench coach Randy Knorr, who gets his turn hitting grounders to the next group. “And I’m probably the worst of the group.”

It is at this intersection — the pitcher throwing pitches, the coaches banging out grounders, outfielders and pitchers shagging fly balls — when batting practice dissolves into its percussive beat. The coaches wait to swing their fungoes until the split second after the hitter in the cage makes contact, just to allow the fielders a chance to protect themselves.

And the fielders, they’ve got issues with which to deal, too, particularly when the team arrives for the first game of a road series. “If the grass is long or if the dirt goes deeper than most,” Desmond said, “just as far as picking out how I’ll position myself, I need to know all that.”

Desmond also scans the stands at an opposing park, trying to find the pertinent info on a scoreboard. Where does it show the count, the number of outs, the speed of a pitch? “You don’t want to be lost out there when the game is going on,” Desmond said.

The ritual

Robledo, who grew up in Panama and spent seven years as a catcher and first baseman in the White Sox organization, is the most popular of the Nationals’ batting practice pitchers, something of the “Iron Byron” of the staff. The group he throws to includes Zimmerman, LaRoche and outfielder Jayson Werth, Washington’s most veteran players. And his task is simple.

“Throw strikes,” he said.

It is both exacting and exhausting. The pitches come in at maybe 55 or 60 mph tops, and each batting practice pitcher throws seven rounds to his group — the first with two bunts and seven swings, the next four with five swings, the final two with three swings each. By that math, Robledo throws roughly 140 pitches per day, perhaps 140 times a year. So over his career, he has thrown nearly 275,000 pitches during official BP sessions alone.

Consistent strikes allow the hitters to handle pitches however they see fit. If they want it inside, they can move in; outside, they can move back. And just as their approaches to hitting during a game might evolve over time, their approaches to BP can change, too.

“I used to be a big fan of flipping the ball the other way,” LaRoche said. “You always hear, ‘See it deep, take it the other way.’ I found out through the years that I was kind of manipulating the ball that way, which is something I would never do in a game. So I’d spend two or three rounds working on bad habits.”

It is Eckstein’s job to identify such habits, and he does so mostly by watching the hitters’ hands, head and legs. Batting practice is mostly for getting timing down, but in order to make sure the timing is right, Eckstein might follow the ball’s flight. “If he’s not using his legs, if he’s not creating a foundation, the ball will die off, tail off,” Eckstein said. “So you’ll get them to get back in their legs, and suddenly they’re getting that extra 15 feet of carry.”

When the ball carries to the outfield, it is pursued not only by the Nationals’ outfielders, who are required to shag flies for one round of hitters. It is, for that hour or so, the domain of the pitchers. Just as hitters might take different approaches in the cage, relievers decide, day to day, how to pass the time. They never hit themselves, so BP might be their only chance to work up a sweat.

“You pick some days where you really want to act like an outfielder,” reliever Drew Storen said, “and there are some days where you’re just worn out and you’re trying to avoid as many balls as possible.”

But each day they stand with the same group. Storen will be in left field with fellow reliever Tyler Clippard, who came over from his right field spot last year. It is a ritual. “There’s nothing you don’t talk about,” Storen said.

But does all this routine make a difference? Depends on the player.

“First of all, hitting a 60-mph pitch, whether it’s left-handed or right-handed, isn’t going to prepare you for a big league pitch,” Zimmerman said. “Some people get caught up in the mental part of it.”

LaRoche, though, said, “It is totally mental.” So particularly when he’s slumping, as he did to start the season, he works hard for the 35 swings he gets on the field. “You’re not totally convinced until you feel it in a game,” he said.

Rarely, though, does a slump reverse itself in a game. That process starts when that gate in the center field wall slides open, the cage emerges and the work begins.

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