A dozen days ago, the Nationals faced a two-week mini-crisis with seven tough games against the Phillies, three against the elite Red Sox and two against decent Tampa Bay. It was time to grind, and win, or else face a real midseason crisis.

Now, the crisis is here. The Nats’ response to their challenge was to play their worst, even though several stars had returned. Also, Manager Dave Martinez illustrates the price you pay for hiring a rookie manager — any rookie — to do on-the-job training with a built-to-win team.

Following Tuesday’s 11-4 loss to Boston, the Nationals have gone 2-9 in that stretch, including 0-5 in one-run games. Their record in such vital games is atrocious: 8-16. That can be an indication of poor managing, tense and panicky play or lack of poised internal leadership. Or statistical randomness.

The Nats will get healthier (soon) and play better (eventually). After the Red Sox leave, 21 of the Nats’ next 27 games are against losing teams. But they have dug a large hole — seven games behind Atlanta in the National League East and 4½ games behind the Phillies for the second wild-card spot . That usually takes two months to erase — if you are very good. To reach 90 wins — which usually puts you in the playoffs and often wins a division — they must go 48-30, which is over .600 ball. Gulp.

That happened fast. But it usually does. Seasons are built on streaks of plus-10 wins over .500 or minus-10 wins under .500. Those quick transitions, such as the Nats’ current 5-16 skid, change the entire shape of a season. Pick the wrong time to plummet, and you spend months mopping up your mess. If you ever get clean at all.

There’s no excuse for the Nats’ recent flop. Don’t say “injuries.” In this period, six of their seven best offensive players — Adam Eaton, Trea Turner, Bryce Harper, Anthony Rendon, Daniel Murphy and (this year) hot rookie Juan Soto — were available every day. Yet in their nine losses, they have scored just over two runs a game. Where would the Nats (21st in runs) be without adding hitting savant Kevin Long?

The Nats have an offensive void at catcher until slightly better Matt Wieters returns. But any sound ship should stay afloat with one cipher in the lineup.

The stars have failed. In his past 65 games, Harper is hitting .197. Over the past five years, Harper ranks 17th in the majors in FanGraphs wins above replacement at 20.2, exactly half of Mike Trout. That seems harsh to me. But between his injuries and prolonged slump seasons, perhaps he’s the 10th best.

With the Nats’ young outfield pipeline, and clear needs next season for a catcher, a second baseman and a starting pitcher, it would be illogical to see Harper in the Nats’ future when they need those funds elsewhere and can semi-replace him in-house. Sometimes you don’t know the ship’s sailed until it’s already out of port.

At least Harper showed solidarity with LeBron James on Monday night, wearing his Lakers hat backward for his postgame interview. Before the game, Harper took groundballs at first base. It’s a whim because the Nats have zero use for him there. It’s in center field that shagging might have a purpose. But under feel-good, let’s-talk-about-it Martinez, whims are not ignored, such as Ryan Zimmerman skipping all but two at-bats of spring training.

Or Murphy not playing for more than a month after doctors said there was no physical reason he couldn’t. For weeks, Martinez made it clear that Murphy was trying to work his way through a mental block, not a physical issue.

Murphy has fair reason to worry and go slowly; recovery from microsurgery is unpredictable. For a few, it’s a career-killer. Also, the Nats agree with Rendon’s view that idleness drives Murphy batty and “he probably loves baseball more than everybody in this room put together.” But the Nats have valid issues, too. They are paying him $17.5 million this year and need to find out before the trade deadline whether his knee can hold up to everyday use at second. It’s a fair request. If he can’t, they need to know.

On Sunday, Martinez finally got testy, saying, “It’s time.” He put Murphy at second base, which strengthens and lengthens the whole Nats attack, for all 13 innings. The next night, he played the whole game at first base. No babying. Murphy responded with his first homer of the year.

Now, Martinez. His no-negativity approach and loosen-’em-up gimmicks such as the “over-the-hump” camels and golf contests in spring training and a DJ in the clubhouse have worked in multiple sports, especially with his mentor of the past decade, Joe Maddon. It’s not wacky. It’s just contemporary. Or trendy.

But handling a bullpen and having a sense of when to hook starters are both basics of the job. Martinez is still mastering them.

Nats relievers knew two months ago they were being pushed to their limits to help the decimated team avoid falling far behind in the division. They took one for the team. Nothing wrong there — but a risk.

Ryan Madson and Brandon Kintzler both went on the DL from overuse. Their 4.40 and 4.31 ERAs might be under 3.00 now, as they usually are, if they’d been worked less. Sammy Solis, in 40 of the Nats’ first 80 games, is back in the minors, told to work on getting better against left-handed hitters. Maybe if he had worked in 32 games, not 40, he would have been getting everybody out.

Perhaps the Nats won two or three extra games early because of Martinez’s aggressive bullpen use. On balance, was it worth it? Tough question. By trading for a fourth top reliever (Kelvin Herrera), maybe that problem is now gone.

My pet peeve, which means there’s an even higher probability than normal that I may be wrong, is “sentimental managing” with starting pitchers who have given a good effort but are not in line to get a win. Yes, pitchers still love stupid “wins.”

In the past 10 days, Martinez has left three starters in games to “give him a chance to get the win.” For the season, his total may be 10. All three recent times the strategy blew up instantly — not proof it was wrong, but still a forehead-smacker. Rookie Erick Fedde was tied, 2-2, with the Phillies after six good innings. He was sent back out, and the first hitter got a double on Fedde’s 99th pitch to knock him out. Fedde got the loss.

Jefry Rodriguez, just up from Class AA, worked four good innings in a 2-2 tie before a rain delay. The Nats’ deep bullpen was fresh enough. After the delay, Rodriguez stayed in and instantly issued a four-pitch walk, then hit a batter. Both scored. Rodriguez was in line for a loss until the Nats bailed him, and Martinez, out.

On sweltering Sunday, a tiring and increasingly wild Gio Gonzalez walked in a run in the fifth inning, cutting the Nats’ lead to 3-1. In my world, it’s time to call the ’pen. But Gonzalez hadn’t gone the five innings to get a win, and Gio popped off once early this season about getting a quick hook. Gio got his five innings, but the Phils got even, 3-3. The Nats lost in the 13th, wasting seven scoreless relief innings.

Martinez always has specific reasons for every such move: low pitch counts, a short bench or lack of available relievers. But the pattern is problematic. The job is to “manage for the 25,” not to make sure that the starting pitchers are contented.

Stories such as this are often contrary indicators, just before a total change of direction. You can make a long list of factors that are looking up for the Nats. But this entire half-season has had sensible predictions that this year wouldn’t be like 2013 or 2015 when the Braves and Mets won the division.

A Nats recovery is still the way to bet. But the team’s problems in tight games and its slipshod handle on the game’s details — both areas where managers are measured — are real and unsettling. So, maybe, lower the ceiling on that wager.

For more by Thomas Boswell, visit washingtonpost.com/boswell