The loss dropped Kansas City to 17-27 and 8 1/2 games back of first-place Cleveland in the American League Central. That includes a mark of 0-6 following scheduled off-days and rainouts, a figure that left manager Ned Yost shaking his head in confusion after the game.
"I don't know, it was just, we just didn't play well tonight," Yost said.
After dodging scoring situations and wiggling his way out of jams en route to three consecutive wins, Royals lefty Bruce Chen finally folded in a tough fifth inning, as he was tagged for five runs without recording an out.
After Xavier Avery drew a leadoff walk, Chen appeared to have him picked off at first base, but Avery broke for second as soon as the throw went to first. The speedy Avery slid in ahead of Eric Hosmer's relay to second for a stolen base.
Then, Robert Andino reached on a sacrifice bunt placed perfectly between Chen and third baseman Mike Moustakas, and deja vu struck. Chen caught Andino off-guard with his pickoff throw to first, but Andino broke for second and made it safely, floating his left arm over the attempted tag with what Yost called a "swim move."
Instead of two out with none on, the Orioles had second and third with none out.
"It would have been huge to get two outs that inning and nobody on base," Chen said. "It's part of baseball. We tried to make good plays and they end up being safe. We should have been able to get out of that inning. I have to make better pitches that inning."
He didn't, and J.J. Hardy and Nick Markakis ended the Orioles' string of small ball, coming through with back-to-back doubles to extend Baltimore's lead to 4-0.
Then, Adam Jones fouled off six pitches with two bats before poking a single to center, ending Chen's night. After Davis singled off Royals reliever Kelvin Herrera to score Jones, Chen's final line was six runs on seven hits and two walks without recording an out in the fifth.
Chen had dodged bullets for three starts and four innings, limiting the O's to just a single run in the first by striking out Chris Davis to leave the bases loaded -- the start of a stretch in which he retired 10 of 11 batters. Chen had limited the damage, but then, in the fifth?
"He gave up the damage," Yost said. "Started getting some pitches over the plate a little bit more."
Aside from some locational misses, Yost said Chen's biggest problem was that he didn't throw enough fastballs. Instead of being between 50 and 55 percent, where Yost wants him, Chen threw fastballs on less than 40 percent of his pitches.
That made it easier for Baltimore to time his offspeed pitches, setting up the big fifth inning.
"When they put those five on Bruce, that was kind of it right there," Jeff Francoeur said. "That kind of opened the floodgates."
On the other side, Hammel kept the Royals mostly at bay with seven strikeouts in six scoreless frames for his sixth victory.
Kansas City had seen Hammel when he was with Colorado, but the pitcher on Friday was a different animal. Butler and Francoeur said the right-hander was throwing faster and with more sink than they recalled.
"He's different than I remember him being," Yost said. "His stuff's better. He surprised me a little bit. We saw it on video, but I wanted to see it live, and he threw the ball well."
Still, the Royals had their chances to take an early lead but couldn't convert. In the second, Francoeur singled, stole second and advanced to third on a throwing error by catcher Matt Wieters. But, with one out, Brayan Pena grounded to second baseman Andino, who charged and threw home to retire Francoeur.
In the fourth, a one-out walk by Moustakas was followed by a double from Francoeur, putting runners on second and third. But Alex Gordon and Pena both struck out to end the threat.
"Offensively we had opportunities and didn't capitalize on them," Yost said. "[We] have to put the ball in play there. We had opportunities to crawl back in early with a big hit here or there."
The Royals also put runners on first and third with one out in the fifth, as Alcides Escobar and Jarrod Dyson both singled, with Escobar taking third on a throwing error by Hammel. After Dyson stole second to move both runners into scoring position, Hosmer struck out and Butler hit a laser to short, where Hardy made a leaping catch to retire the side.
"It was huge, because they could have opened it up right there," Hammel said. "It was a huge turning point."
"I couldn't hit a ball better," Butler said. "Can't hit the ball harder than that. It just wasn't in the right spot. I can't change anything on that."
When Francoeur capped off a 3-for-4 night with a two-run home run at the end of a 13-pitch at-bat in the eighth to get the Royals on the board, it was much too little, much too late.
All that's left is to look to Saturday's game, where the Royals hope similar opportunities will have different outcomes.
"If we keep giving ourselves those chances, obviously we're a good enough hitting team that people will come through," Francoeur said. "It just didn't happen tonight."