PHOENIX -- Hyun-Jin Ryu’s recent struggles continued Thursday night against a National League West rival that he had dominated this season.

The Dodgers’ All-Star left-hander gave up a season-high-tying seven runs in a series-opening 11-5 loss to the D-backs at Chase Field. It marked the second straight start that Ryu gave up seven runs, and the third time this year.

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After allowing more than two earned runs only once in his first 22 starts, Ryu has allowed at least four in three straight outings, posting an 11.05 ERA over that stretch. The left-hander entered Aug. 17 with a 1.45 ERA, but that mark is now up to 2.35.

“I understand that it’s three in a row that he hasn’t thrown the way he’s thrown all year, but it’s something for us where it’s not too far off,” Roberts said. “I think, just seeing the way the baseball comes out of his hand, velocity’s still there, missing just off. I don’t think it’s a fatigue thing, just the way he looks and talking to him, he’s very strong. I don’t see that there’s a drop-off in stuff, I think the drop-off is just a little bit of that command.”

Ryu went 3-0 with a 0.45 ERA in his first three starts against the D-backs this year, which included seven scoreless innings against them in his return from the injured list on Aug. 11. He then got off to a strong start Thursday, retiring nine of Arizona’s first 10 batters in three scoreless innings.

But the D-backs plated four runs while sending nine batters to the plate in the fourth, which included a two-run double by Wilmer Flores, an RBI double from Nick Ahmed and a pinch-hit RBI single by Ildemaro Vargas.

Ryu retired the first two batters of the fifth before giving up five consecutive hits, including a two-run double to Adam Jones and an RBI single to Ahmed. Carson Kelly’s single to finish that stretch was Ryu’s season-high-tying 10th hit allowed, and it ended the left-hander’s night. Ryu also gave up 10 hits in a win over the Pirates on May 25.

“August has been tough for me, obviously, but my job is to go out there every fifth day, and I just have to go out there and prepare for the next start,” Ryu said through an interpreter. “Despite the result, I think my command wasn’t as bad as the last two games that I pitched.”

Since his return from the IL, Ryu has gotten an extra day of rest before his starts as the Dodgers have opted to go with a six-man rotation. Roberts said the plan is for that to continue moving forward.

“I see him making his next start. We’re going to talk about it, but the plan is for him to make that start,” Roberts said. “The last couple times, we’ve given him an extra day, so that’s probably how we’re going to go right now.”

One of the front-runners for the National League Cy Young Award, Ryu’s tough stretch is happening as the Dodgers have a commanding 19-game lead in the NL West and are closing in on clinching the division; their magic number is at nine. However, it could hurt Los Angeles’ rotation depth for the playoffs if he doesn’t get his breakout season back on track.

Ryu has pitched 157 1/3 innings this season, his most since pitching 192 during his 2013 rookie campaign. But Roberts remains confident that the left-hander will return to form this year.

“You can’t expect to go out there and go 27 starts and be flawless,” Roberts said. “He’s going to be just fine.”