The Post Sports Live crew looks at the issues plaguing the Washington Nationals, including injuries to Bryce Harper and Stephen Strasburg and the team’s poor defense. (Post Sports Live)

When a manager greets a rainout with glee, and hopes for another, it’s possible there is a problem with his ballclub. In fact, it’s a certainty: The 2013 Washington Nationals are struggling to match their success of 2012.

This is not an unusual state of affairs in baseball, which plays 162-game seasons for a reason. But the way the Nats are playing has furrowed the collective brow of Washington. The team, plagued by injuries, has dropped to third in the NL East. More troubling to Nats fans (and I don’t want to get too sabermetric-y here): They can’t hit, pitch or field with anything approaching consistency.

This has sent Nats fans — and the Nats organization — for a roller coaster ride they were not expecting after last season’s first trip to the playoffs. Thus Tuesday night’s walk-off sacrifice fly to beat the Mets was greeted by some as the turning point in the season. Players mobbed the infield, leaping about as if they each had two healthy hamstrings. Problem solved! Huzzah!

Then came the next night, a 10-1 loss to the Mets, and there was no infield cavorting. It was clear that Steve Lombardozzi’s hard-fought at-bat and game-winner 24 hours previously had not created a sea change in the Nationals. And it was unreasonable to expect that it could. Instead, it was just business as usual for the Nats: win one, lose one. Don’t hit. Hope for good starting pitching. (Tuesday they got it from Jordan Zimmermann; Wednesday they didn’t get it from Dan Haren.)

Part of the Nats’ struggles can be attributed to injuries, of course. They didn’t have this many a year ago, certainly. But the baseball gods giveth, and the baseball gods taketh away Bryce Harper and Stephen Strasburg. Now Dr. James Andrews has been summoned. The parallels between Harper and Robert Griffin III are growing eerier by the minute. (You know, Lincoln’s secretary was Kennedy; Kennedy’s secretary was Lincoln.)

The Post Sports Live crew debates whether it’s better for the team if injured Nationals play through the pain. (Post Sports Live)

The truth is, the Nats’ issues go far deeper than anything an MRI will find. To put it bluntly, they are playing poorly many nights. “This is a simple game,” said a wise man once upon a time. “You throw the ball. You catch the ball. You hit the ball. Sometimes you win. Sometimes you lose. Sometimes it rains.” Tuesday night they won. Wednesday night they lost. Thursday night it rained. I mean, “Bull Durham” has all the answers.

But for the Nationals, the game has been anything but simple this season. After rolling through 2012 with joy and verve, 2013 has been, at times, more of a painful slog. Entering Friday night’s games, the Nats were 28th out of 30 teams in batting average (.230), 30th in on-base percentage (.287), 27th in slugging percentage (.372), 29th in runs scored. Their fielding percentage was 28th, and they had committed the second-most errors in baseball.

Their team ERA is a very respectable sixth (3.63), which should have them in better position in the win column. Before Friday’s game, their starters had a 3.41 ERA and if you drop Dan Haren — tempting — it falls to 2.93. The bullpen has been more spotty. Much more spotty. The ERA for starting pitching is 3.41; for the relievers it’s 4.13.

Fixing all this seems like a lot to expect from Anthony Rendon and Ian Krol, although many fans were happy to see Danny Espinosa dislodged from the lineup. The Nats have given Espinosa plenty of opportunities — 390, in fact — but this season’s .158 batting average, .193 on-base percentage and .272 slugging percentage (not to mention 47 strikeouts) indicate that isn’t happening.

Harper and Strasburg on the disabled list, Andrews called on the Bat Phone from his secret lair, Gio Gonzalez being interviewed in MLB’s drug investigation, a batting lineup that can’t hit, a bullpen that hasn’t jelled — that’s a lot of woe for one team.

But is it time to change the seventh-inning stretch sing-along from “Take On Me” to “Gloom, Despair and Agony on Me”? (For those not fortunate enough to grow up in the “Hee Haw era, it goes something like this: “Gloom, despair and agony on me/deep dark depression/excessive misery. If it weren’t for bad luck I’d have no luck at all. Gloom despair and agony on me.”)

What’s strange about the 2013 Nats is that, despite all these problems, despite a lack of consistency and a long list of injuries and some troubling fielding from Ryan Zimmerman and all the other problems that have cropped up this season, it still seems premature to write them off. If they get healthy (not so hard) and stay healthy (much harder), and if Rendon adds a spark to the lineup and if the team can find a way to use the bullpen with success and if the team can start hitting again — and that’s the biggest “if” of all — the Nats could go on a run.

There are 27 games in July. Let’s say they win 15 or 16 of those. They should be able to jockey their way into position for a run at the NL East title. I can see that happening, and I have no reason to be unduly optimistic about the Nats (or anything, for that matter).

Yet I can just as easily see more of the same — win, loss, rainout, rinse, repeat — leaving us with a long July and August and making the Nats once again invisible once football starts. One thing is certain: It’s going to take more than a walk-off sac fly to save this season.