SEATTLE (AP) -- Seattle starter Hisashi Iwakuma added to his dominant streak against the AL Central.
The All-Star right-hander struck out seven and walked none in eight innings to run his scoreless streak against division teams to 48 2-3 innings in the Mariners' 1-0 win over the Kansas City Royals on Thursday night.
It is the second-longest streak by any pitcher against one division dating to 1974. Orel Hershiser tossed 55 straight scoreless innings against NL West opponents in 1988.
''He's got a good two-seamer and his split was pretty much unhittable today,'' Kansas City's Billy Butler said. ''He was mixing a slider in there and had all three pitches working at any time. He was throwing them all for strikes.''
Iwakuma (2-0) scattered four singles and allowed only one baserunner to reach second in his second start of the season. Iwakuma, who began the year on the disabled list with a strained tendon on the middle finger of his pitching hand, bolsters a strong pitching staff that has helped the team win 11 times in the last 14 games since losing eight straight from April 15-22.
''He's getting better each and every time out,'' Mariners manager Lloyd McClendon said. ''I think if you asked him, there's a lot more in there. There's a lot of room for improvement, but that just goes to show how good he really is.''
Despite limiting the Mariners to just two hits and one run in six-plus innings, Danny Duffy (1-3) was the hard-luck loser for Kansas City. He has allowed two hits and a run in each of his first two starts this season after pitching out of the bullpen to begin the year. Both times he has been stuck with the loss.
The Mariners pushed across the lone run in the third. Mike Zunino led off with a double for Seattle's first hit and moved to third on a sacrifice bunt. After a strikeout, Duffy intentionally walked Robinson Cano. Corey Hart followed with a run-scoring single up the middle that proved to be the difference.
Seattle hitters have driven in runs three out of the six times opposing teams have intentionally walked Cano this season.
''Offense didn't win the game, Kuma obviously was dominant,'' Hart said. ''Any time a pitcher throws like that, you try to scrap any run you can get across, and one was enough. A guy throws like that, you hate to lose.''
Kansas City managed just four singles and advanced a runner to second base only once during the first eight innings. The Royals had their best opportunity to score in the ninth when Fernando Rodney walked two, but the closer struck out Butler and induced a game-ending groundout.
Rodney's 10th save in 11 chances kept the Royals off the board for the 27th straight inning, a streak that dates to September 2013.
''Our guys are grinders,'' McClendon said. ''I think they've proven that they know how to get back up off the mat, so to speak. This has been a tough month and a half for us in a lot of different ways, but I think when it's all said and done, maybe we're not as bad as people thought we were going to be.''
NOTES: Seattle LHP James Paxton, on the DL with a strained left lat muscle, played catch and is scheduled to throw a bullpen session Friday. ... Mariners RHP Taijuan Walker is scheduled to toss in the bullpen Sunday after playing catch on Thursday. Walker is on the 15-day DL with right shoulder inflammation. ... Royals 2B Omar Infante was not in the lineup for the second consecutive day due to back spasms. Manager Ned Yost said the team doesn't think Infante will have to go on the DL. Infante is day to day.