WASHINGTON -- Yes, the D-backs lost to the Nationals, 15-5, on Sunday afternoon, a clunker of an ending to their successful East Coast swing, but of larger concern is what Arizona is going to do with its rotation going forward.

“We know this is a spot that needs to be figured out,” D-backs manager Torey Lovullo said. “It’s the biggest thing that I’ll be thinking about over the next 48 hours.”

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With Jon Duplantier out due to right shoulder inflammation, the D-backs needed a starter to take his place Sunday, so they turned to reliever Archie Bradley, who had not made a start since Oct. 1, 2016.

It didn’t go well as Bradley allowed three runs in the first inning and four runs total in just 1 1/3 innings.

“I don’t know if disappointed is the right word,” Bradley said. “I mean it stinks to give up those runs after taking an early lead and put us in a hole and not be able to go at least two or three. But I felt like I made some good pitches. The things that I’ve been working on -- my command -- I threw some balls where I wanted to. They just did a better job hitting them, really.”

Bradley had been pitching better of late, having not allowed a run in his previous four relief outings.

One of the reasons for the success has been the addition of a changeup to go along with his fastball and curve. However, the Nationals jumped on Bradley early in counts before he could get to the change.

That prompted a question to Lovullo about whether Bradley may be tipping his pitches.

“We’ve looked at him, we’ve examined as much as we possibly can,” Lovullo said. “I think at one point in time he was, but that’s a good question. That’s a very valid question. We’re always watching for that.”

After Bradley, the D-backs then went with Zack Godley, who had been a candidate to start the game. Godley had begun the year in the rotation, but after struggling he was shifted to the bullpen.

Godley did give the D-backs the length they needed Sunday by going 4 2/3 innings, but he allowed six runs on seven hits.

The D-backs will go back to the drawing board to find a starter. Lovullo said even with Monday’s off-day, the team does not plan on simply skipping that spot in the rotation next time through.

In addition to Godley, the D-backs do have candidates with Triple-A Reno like veteran Ricky Nolasco, Matt Koch, Alex Young and Taylor Widener.

The team did have talks with the Mariners about acquiring veteran right-hander Mike Leake, but those seemed to have fizzled.

One thing that seems unlikely is the D-backs spending a lot of prospect capital on a pitcher, because while they are still in the National League Wild Card race, they are not nearly as willing to deal young players for help as they have been the previous two seasons.

On the bright side for the D-backs, they finished the 10-game trip, which also included stops in Toronto and Philadelphia, with a 7-3 mark.

“I think overall it was a very good road trip, and I’m proud of these guys,” Lovullo said. “You’ve got to just throw this one out as quickly as you possibly can. I wish Archie had done better, but just unfortunate that it didn’t work out the way we wanted it to.”

Another huge positive was that Ketel Marte finished the road trip just like he started it -- red hot.

Marte was a triple shy of hitting for the cycle Sunday and wound up with two doubles, seven homers and 14 runs scored on the trip.