Some of the Nationals’ worst qualities converged today and made for another lopsided loss in a season that already had included too many of those.

Mitchell Parker’s propensity for early struggles was on full display. So was his continued inability to field routine comebackers toward the mound. Add some more sloppy infield defense to the mix, and you’ve got the perfect recipe for a game that was well out of hand before many in the crowd of 34,319 had a chance to get settled in at Nationals Park.

This 10-3 loss to the Red Sox ranks right up there with the ugliest of the season. It’s the ninth time in 89 games the Nats have lost by seven or more runs, the third time in five games on this current homestand.

To win Sunday’s finale and avoid a sweep at the hands of Boston, they’re going to have to get a whole lot better of a performance from the pitcher they promote from their farm system to take over the rotation spot Trevor Williams held until landing on the 15-day injured list this week with a sprained elbow: Shinnosuke Ogasawara.

Manager Davey Martinez announced this evening the Japanese left-hander will be promoted from Triple-A Rochester to make his major league debut, selected over top prospect Cade Cavalli (who gave up seven runs over three innings in his most recent minor league start). Ogasawara, the first free agent the Nationals have ever signed directly out of Asia, opened the season at Triple-A but only recently returned from a two-month stint on the injured list with an oblique strain. The 27-year-old, who signed a two-year, $3.5 million contract, faces a stiff challenge in his debut.

"He went down there, he understood what he needed to do," Martinez said. "Before he got hurt, he was throwing the ball pretty well. He got hurt, he's coming back, he's throwing the ball well. We get him here tomorrow, we'll see what happens. ... Strikes. Strikes. Throw strikes."

The themes throughout most of the Nats’ lopsided losses have remained the same: Poor pitching and poor defense. Both were all too common during the first three innings of today’s game.

Parker, who already has battled a first-inning hangup throughout the season, immediately found himself in trouble this afternoon when Brady House booted Nate Eaton’s leadoff grounder to third for the first error of his brief major league career. Parker responded by serving up an RBI double to Romy Gonzalez, then another RBI double to Rob Refsnyder two batters later, leaving himself in a 2-0 hole after a 30-pitch top of the first.

The left-hander would settle down during a quick top of the second, but it all fell apart for him in the top of the third, an inning that saw seven runs score via seven hits, another error and another play not made by an infielder.

"Reel it back in, that's the name of the game," he said. "Try and limit the damage. Today, I obviously didn't do a decent job."

Parker was mostly to blame, from the two doubles, one triple and one homer he surrendered during that inning. But there were also a couple of defensive miscues, from first baseman Nathaniel Lowe’s inability to cleanly field Eaton’s grounder to his left (turning it into a double) to the latest fielding gaffe by Parker himself. (Lowe was charged with an error in the eighth that led to another run.)

In this case, the lefty had a golden opportunity to get out of the inning with only three runs scoring when Abraham Toro tapped a routine comebacker toward the mound. Parker completely misplayed the ball, allowing a run to score. His next pitch was clobbered by Ceddane Rafaela to left for a two-run homer, and two more hits came after that.

"We know Mitchell's still a very young pitcher," Martinez said. "Once things start unraveling, something happens, he's got to be able to control the heartbeat, slow things down a little bit. He hasn't done it. When he gets out of that first and second inning, he usually figures it out and gets through the game."

It was Parker’s seventh charged error in only 17 career fielding chances, a major flaw that hadn’t come up as often this year as last year but remains a huge concern.

"That sucks," he said. "I've got to be able to field my position."

This also was the fourth time in seven games the Nationals have given up at least six runs in an inning, a disturbing trend that has rendered several previously competitive games lost causes.

To his credit, Parker gutted out another three innings (all of them scoreless) after the disastrous top of the third and at least saved an already-taxed bullpen from even more work. In the process, he became only the third pitcher in club history to give up nine runs (only four were earned in this case) while completing at least six innings, a list that until now had included only Jerome Williams (2007) and Tanner Roark (2018).

"What he did after (the third inning) was really impressive," Martinez said. "Six innings at 95 pitches really saved our bullpen. That's what we need from him at the start of the game."

The settling down of the pitching staff today provided an opportunity for the Nationals lineup to mount some kind of comeback. Down nine runs, it was too much to ask for a full rally all the way back, but they did scratch out three runs against Red Sox starter Walker Buehler, who actually wound up throwing more pitches (100) in fewer innings (five) than Parker.

"Keep fighting. Just keep playing baseball," said right fielder Daylen Lile, who extended his hit streak to 12 games with a fourth-inning single off Buehler. "Try not to get too down. Know that at any moment, we can turn it around."