LOS ANGELES — Dodgers right-hander Yoshinobu Yamamoto was placed on the 15-day injured list before Sunday’s game against the Kansas City Royals with tightness in the triceps of his pitching arm.

Manager Dave Roberts said Yamamoto, 25, would undergo testing Sunday to determine the severity of the injury and a recovery timeline.

“He’s a guy that we’re still trying to learn a lot about, and appreciate the fact that the most important time of the season is yet to come,” Roberts said. “His health is paramount. So for us to be proactive and put him on the IL seems like the smartest thing.”

Yamamoto, playing his first year in the majors after departing his native Japan and signing a record $325 million, 12-year contract, is 6-2 with a 2.92 ERA.

Yamamoto left Saturday’s loss to Kansas City after two innings. He said through an interpreter after the game that his scheduled start the previous Thursday against Texas had been pushed back because of the tightness.

He also said the tightness was gone for most of Saturday, but he started feeling it again when he was warming up before the game.

Yamamoto threw two-hit ball over seven innings at the New York Yankees on June 7. He tossed 106 pitches, the fourth straight time he had thrown more than 100.

Roberts said he has been mindful of Yamamoto’s pitch count, but also noted Yamamoto was used to throwing 120 pitches or more when he pitched in Japan.

With Bobby Miller returning to the rotation for Wednesday’s game at Colorado, the Dodgers will still have a five-man starting staff. Clayton Kershaw will also make his first rehab start this week.

Los Angeles’ rotation went into Sunday’s game with the majors’ seventh-lowest ERA at 3.49.

The Dodgers also placed right-hander Michael Grove on the IL with a right intercostal strain. Right-handers J.P. Feyereisen and Michael Petersen were called up from Triple-A Oklahoma City. To make room for Petersen on the 40-man roster, right-hander Joe Kelly was transferred to the 60-day IL.

BOSTON — New York Yankees top prospect Jasson Dominguez was placed on Triple-A Scranton/Wilkes-Barre’s injured list Sunday with a left side injury.

Yankees manager Aaron Boone said Dominguez suffered the injury on an “awkward” checked swing in his third plate appearance Saturday. He finished the at-bat, striking out looking, and played another inning in center field before he was removed from the game. He went 1-for-3 with a stolen base and two strikeouts.

“He’s getting testing today,” Boone said before the Yankees faced the Boston Red Sox on Sunday. “But it’s enough to put him on the IL right away at least. I’m sure we’ll have an idea — hopefully have an idea — with what exactly we got by tonight or [Monday].”

One of the more heralded prospects in recent years, Dominguez, nicknamed “The Martian,” made his major league debut last September before his 21st birthday. He played in eight games for the Yankees, batting .258 with four home runs, before tests revealed a torn ulnar collateral ligament in his right elbow. He returned to the field after surgery in mid-May on rehab assignment.

The rehab assignment ended Wednesday when the Yankees, who have a surplus of outfielders, activated Dominguez from the 60-day injured list and optioned him to Scranton/Wilkes-Barre. Dominguez slashed .389/.405/.609 in nine games in Triple-A before the injury.

Dominguez was in the outfield for Gerrit Cole‘s dominant rehab start Friday for Scranton/Wilkes-Barre. The question now is whether Cole’s next outing will be his season debut in New York this week.

The Yankees are choosing between having Cole and Cody Poteet start Wednesday against the Baltimore Orioles at Yankee Stadium. The team has “TBA” listed for now.

“I think we’re just going to get through today and probably make it tonight or certainly [Monday],” Boone said.

Cole, 33, has made three rehab starts since returning to game action after being diagnosed with nerve irritation and edema in his right elbow in mid-March. On Friday, the reigning AL Cy Young Award winner held the Rochester Red Wings to one unearned run on two hits over 4⅓ innings. He struck out 10, walked none and threw 68 pitches. In all, he has given up two runs (one earned) across 12⅓ innings in his rehab showings.

“We don’t have to make that final call right now,” Boone said. “He’s going to pitch, probably in that five- or six-day window coming off his last one. Let’s just not tie ourselves to something until really we have to.”

HOUSTON — Ronel Blanco had the second hitless outing of his brief major league career but was pulled after seven innings as the Houston Astros beat the Detroit Tigers 4-1 on Sunday.

Manager Joe Espada shared part of the conversation he had with Blanco when he removed the dominant right-hander from the game.

“I just told him how proud I am of what he’s doing,” Espada said. “This is a guy that came out of nowhere and he continues to perform at a high level. He has really picked his team up through injuries and he goes out there and he does things we need him to do.”

Blanco (7-2), who threw the only no-hitter in the majors this season April 1 against Toronto, was just as good this time in the 20th start and 37th appearance of his career. The 30-year-old threw 94 pitches with 65 strikes and tied a season best with eight strikeouts. He walked three.

“I was just attacking the strike zone,” he said through an interpreter.

Ryan Pressly replaced Blanco to start the eighth and gave up the Tigers’ first hit, a two-out single by Wenceel Perez.

Jose Altuve hit a three-run homer for Houston.

Blanco is the second pitcher in franchise history to have two starts with at least seven hitless innings in the same season, joining Framber Valdez, who did it last year.

The Tigers couldn’t do much of anything against Blanco a day after they had a season-high 19 hits in a 13-5 trouncing of the Astros.

Blanco didn’t allow a baserunner until he walked Gio Urshela with two outs in the fifth.

He then walked Akil Baddoo and Carson Kelly to load the bases, but retired Zach McKinstry on a flyout.

Espada said it wasn’t a difficult decision to replace Blanco because of how many pitches he has thrown this year, noting that he has had four outings with more than 100 pitches and two with 98.

“But did I want him to be more efficient earlier and give him a shot? One hundred percent,” Espada said.

Blanco said he wasn’t upset when Espada took him out.

“I threw a lot of pitches and I wasn’t going to be able to finish it,” he said. “So, I just accepted it.”

Blanco made a good defensive play for the second out of the sixth when he grabbed a comebacker hit by Matt Vierling. He then sat down Riley Greene on a popup.

Urshela reached with two outs in the seventh on a throwing error by third baseman Alex Bregman. Blanco then retired Baddoo on a fly ball that center fielder Jake Meyers caught on the warning track.

“We did battle,” Tigers manager A.J. Hinch said. “We obviously couldn’t get anything started against him. The three walks, you have a chance with two outs, but he wiggles out of it. And then he just continued to hit spots and threw a lot of different pitches.”

After the hit by Pérez, Pressly sat down Vierling before Josh Hader took over for the ninth. Mark Canha singled with one out and scored on a double by pinch hitter Andy Ibanez.

Urshela grounded out and Hader struck out pinch hitter Jake Rogers to end it.

Detroit starter Kenta Maeda (2-3) permitted five hits and four runs in five innings.

Altuve hit a leadoff single before moving to second on a wild pitch with one out. The Astros took a 1-0 lead when he scored on a single by Yordan Alvarez.

Mauricio Dubon singled with one out in the second and Chas McCormick drew a two-out walk. Altuve made it 4-0 with his shot to center field.