Kansas City Royals starting pitcher Zack Greinke delivers against the Baltimore Orioles. The Royals won, 8-1, Friday in Kansas City, Mo.

Kansas City, Mo. ? Zack Greinke pitched seven innings to earn his seventh win, Miguel Olivo hit a three-run homer, and the Kansas City Royals ended a six-game losing streak with an 8-1 victory over the Baltimore Orioles on Friday night.

The Royals battered Adam Eaton (2-4) to stake Greinke to a 6-1 lead by the fourth inning, and the right-hander overcame some shaky moments after a lengthy rain delay to match Toronto’s Roy Halladay for the AL wins lead. Mike Jacobs hit his eighth homer, Jose Guillen and Alberto Callaspo drove in two runs each, and Mark Teahen had three of Kansas City’s 13 hits.

Baltimore, still without outfielders Adam Jones (hamstring) and Luke Scott (shoulder), missed some early chances against Greinke and had two hits after the third inning to lose for just the eighth time in its past 32 games in Kansas City.

The return of Zack-mania to Kauffman Stadium — well, that and the $1 hot dogs and peanuts on Buck Night — had the Royals expecting a sellout. Thunderstorms moved into the area late in the afternoon, delaying the start by 2 hours, 30 minutes, and keeping several thousand fans away.

Those who showed up — about 25,000 — waited out the storms by milling around the concourses and filling the new sports bar, creating a frat-party atmosphere before the first pitch.

Greinke (7-1) had his nine-game winning streak snapped against the Angels on Saturday, yet was still sharp, allowing one run and four hits in eight innings. Greinke didn’t have the same kind of stuff early against the Orioles, walking two, including Brian Roberts to lead off the game, and allowing one more hit in the first three innings than his previous start.

But after giving up a run on Aubrey Huff’s single in the third, Greinke got into a groove, retiring 11 of the next 12 batters before leaving after 106 pitches. He allowed six hits, struck out six and saw his baseball-best ERA creep up to 0.60.

Eaton had problems after the rain delay, too. He just never fully recovered.

The right-hander labored through a 29-pitch first inning, giving up a two-run single to Guillen not long after Billy Butler’s foul pop fell between third baseman Melvin Mora and catcher Gregg Zaun.