Anthony Rendon, left, and Ryan Zimmerman, along with Bryce Harper and Daniel Murphy, have formed a dominant middle of the order for the Nationals this season. (Katherine Frey/The Washington Post)

Sometimes it’s hard to see what’s right in front of you. Especially if it’s good. Like the amazing seasons being amassed by the heart of the Washington Nationals’ batting order: Bryce Harper, Ryan Zimmerman, Daniel Murphy and Anthony Rendon.

Three of them will be in the starting lineup for the National League on Tuesday night in Miami at the All-Star Game and, as Harper said Sunday, “Anthony should be starting at third base for the National League this year.”

But even all-star accolades don’t quite give a sense of what this quartet has done, compensating for plenty of injuries and a catastrophic bullpen, to bring Washington to the all-star break with a 9½ -game lead in the NL East over Atlanta after thumping the Braves, 10-5, at Nationals Park on Sunday.

The glamour measuring stick of this era is on-base-plus-slugging percentage — or OPS — and it is a good one. Certainly better than the Triple Crown categories of home runs, RBI and batting average that monopolized conversation for a century. Any number near 1.000 for a career is Hall of Fame.

Right now, Harper (1.021), Zimmerman (.969), Murphy (.966) and Rendon (.960) stand second, fourth, fifth and seventh in the NL.

In this century, no World Series team has had four players (with enough plate appearances to qualify for the batting title) who all had an OPS of .900 — much less four at .960.

On Friday night, the Nats trailed 4-1 in the ninth. The previous 128 times the Nats had trailed by three runs or more in the ninth, going back several years, they lost. But this is the Nationals’ offense of 2017, which has scored 10 or more runs 15 times and has had games of 23 and 18 runs.

“You can feel the pressure building up in this lineup until the dam breaks,” Zimmerman said. On Friday, Harper singled, Zimmerman walked, Murphy and Rendon singled, and a sacrifice fly by Matt Wieters tied the game. In the 10th inning, Zimmerman singled a man from first to third, then Murphy walked Atlanta off with a blast over the left fielder’s head.

On Sunday, as the Braves hoped to leave town with three wins in four days to cut their division deficit to 7½ games, the Nats’ quartet reached base 10 times, scored six runs and drove in six more. Just a day at the office. “We all have a pretty good sense of the game,” Zimmerman said after Sunday’s win. “It doesn’t make you feel like you always have to be the one who comes through.”

Because of them, the Nats are scoring 5.52 runs per game, which puts the team on pace to score 895 runs this year. That would break the franchise record by . . . come on, guess . . . hint, guess very high. By 132 runs.

Nobody has seen scoring like this by any major league team in Washington since 1936. So ask Nats owner Ted Lerner to tell you about it. He was 10.

Before we get carried away, there have been a few teams that have scored 1,000 runs. And quite a few Yankees teams have topped 895. But, for context, the Braves have been playing in one town or another since the 19th century. Only one Braves team since 1897 has scored at a pace higher than the 2017 Nats. Only one Orioles team since they came to Baltimore in 1954 has scored more than this.

Because Adam Eaton, Jayson Werth and Trea Turner have missed so much time with injuries and Nationals catchers have added modest offense, an inordinate amount of the task has fallen to the Big Four.

They are, in the following order — Harper, Zimmerman, Murphy and Rendon — hitting .325, .330, .342 and .304 and are on pace for 120, 116, 118 and 99 RBI, as well as 37, 35, 26 and 29 homers.

“When you have that [many] hitters together . . . you feel very comfortable wherever you hit in the lineup,” said Nationals Manager Dusty Baker, who was on a Los Angeles Dodgers team in 1977 that had four 30-plus home run hitters, including him. “The opposition knows you’re capable of exploding for a lot of runs in a short period of time. You feel like you’re never out of a game. That’s primo right there.”

The Nats have their problems. Except for unexpected veteran Matt Albers (1.93 ERA) and young lefty Enny Romero (3.63), who fanned Freddie Freeman and Matt Kemp on 101- and 100-mph fastballs Sunday, the bullpen should be in handcuffs. Fifth starter Joe Ross, who has looked worrisome all season, left Sunday after getting just 10 outs with what Baker called “triceps tenderness” and was sent for an MRI exam as the Nats — who have gotten little good news from such tests — fretted.

But any team with two dominant aces such as all-stars Max Scherzer and Stephen Strasburg — who are on pace for 322 and 238 strikeouts — as well as that crunching four-man heart of the order, has the potential to arrive in October with a dangerous package, especially if trades help the bullpen.

Werth is expected back in 10 days, perhaps for the series in Arizona, and recently injured Michael A. Taylor not too long after that.

Unfortunately for the Nats, they cannot mummify Harper, Zimmerman, Murphy and Rendon until October, then unwrap them all at the perfect moment — healthy and hitting in a row, left-right-left-right — like demons. Fingers must be crossed and form maintained.

If you watch the All-Star Game on Tuesday, pull for NL Manager Joe Maddon to bat Harper, Zimmerman and Murphy in a row — three-quarters of the best heart of the order that Washington has seen since the 1930s and better than some franchises ever have provided for their fans.

This is a hitter’s year. Records will be broken and new standards set. You might see Rendon go 6 for 6 with three homers and 10 RBI. Or the scoreboard show “23” or “18” in the runs column. Or a bottom-of-the-ninth comeback you hardly believe. Or seven walk-off wins by the all-star break. Oh, we’ve already seen all that.

Don’t say, “It can’t happen.” This year, it can, all over baseball. And the Nats are right in the middle of it.