WASHINGTON -- Dodgers manager Dave Roberts said before Sunday’s 11-4 loss to the Nationals at Nationals Park that backup for the middle infield may need to come via trade. The recent injury to utility man Enrique Hernández and the long-term absence of Chris Taylor means there’s no depth in the middle of the infield, and it has also forced Max Muncy -- the usual everyday first baseman -- to move over to second for the time being.

Until that need is addressed, the Dodgers have shifted career outfielder Joc Pederson to first base. Pederson has struggled learning the position on the fly, no more evident than in the sixth inning of Sunday’s loss.

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After starter Walker Buehler found himself in a bases-loaded jam with one out, a potential double play ball found Pederson at first. His throw home bounced through catcher Will Smith’s legs, allowing two runs to score and tagging him with an error. Two batters later, an Anthony Rendon popup into shallow right couldn’t be corralled by Pederson, taking any and all wind out of the sails for a Dodgers team looking for a sweep in D.C.

The Dodgers have now committed 77 errors on the season, which leads the National League. Twenty of those mistakes have come in the 15 games since the All-Star break.

“It’s something that shouldn't slump,” Roberts said. “We are not playing consistent defense. When you don't make plays, it adds to pitch counts and things like that. It really changes the dynamic of a game. I know the preparation is there, and we just have to get better. It’s pretty simple.”

Granted, that popup in the sixth was no easy sequence. Pederson had to twist and turn his way to try to find it in the sun, and he was not charged with an error on the play. Yet with an exit velocity of 70.8 mph and launch angle of 60 degrees, Statcast gives similarly hit balls an expected batting average of just .010.

“Could have happened to anybody,” Roberts said.

As for the error throwing home, however, the manager said “[Pederson] had time and he just didn’t make a good throw.”

The Dodgers have already made a trade to improve their infield depth, acquiring Tyler White from the Astros last week. But with White not expected to make his Dodgers debut until the team lands in Colorado on Monday, David Freese placed on the injured list Friday and Muncy taking over at second, additional options are limited.

Enter Pederson, who made his first career start at first base on June 21. His FanGraphs-measured defensive rating, which ranks a player’s defensive value relative to league average, sits at -2.6 -- tied with Freese for worst on the Dodgers with more than 100 fewer innings played.

“He didn’t make a play today,” Roberts said, “but the team defense isn’t solely on one person. That’s collective. [We] try to give him opportunities to continue to get better, and we’ve seen that. This certainly is not on him.”

Another defensive lapse -- Alex Verdugo double-clutching a relay throw -- allowed Victor Robles to take home in garbage time. Still, Sunday’s fumbling cannot be attributed solely to the defense. Stephen Strasburg set down the first 13 Dodgers he saw in order. He and the Nationals’ bullpen combined to hold the Dodgers to just four hits and four runs, three of which came via a 441-foot long ball from Corey Seager when the game was already well out of hand in the ninth.

Strasburg far outshined Buehler, who saw a career-high seven runs (four earned) cross the plate during his 5 1/3 innings -- on his birthday, no less. The last time seven runs crossed home plate on Buehler’s watch came just four starts ago in Denver.

On Sunday, both teams had their problems with home-plate umpire Jeremie Rehak. Buehler expressed his displeasure from the mound and Roberts had to race out to protect Justin Turner after Strasburg struck out the side in the sixth. The Dodgers’ moments of dissatisfaction came after Nationals manager Dave Martinez and Adam Eaton were ejected in the first inning.

Regardless, the Dodgers, content with taking two of three against the red-hot Nationals, now head to Coors Field and the Rockies where they’ll watch Wednesday’s Trade Deadline come and go on Mountain Time. During that series the questions surrounding infield depth, and more, will be answered one way or another.