The Orioles were within striking distance of their fourth straight victory when the bullpen door opened and Brian Matusz entered the game.
Soon after that, Baltimore's window of opportunity closed.
Mike Moustakas hit two home runs, including a grand slam, and finished with a franchise-record nine RBIs as the Kansas City Royals beat Baltimore 14-6 Saturday.
Moustakas singled home two runs in the sixth inning, hit his second career slam in the seventh and capped his record-setting performance with a three-run drive in the ninth.
Each of those hits came off a Baltimore reliever. It was the second straight shoddy performance by the Orioles' bullpen, which was also ineffective in a 14-8 win over the Royals on Friday night.
"We didn't pitch well out of the `pen, obviously," manager Buck Showalter said. "A couple of games, I'm being nice when I say they weren't crisp. Both of them."
Baltimore held a 4-1 lead before Kansas City batted around in a five-run sixth against three pitchers. After Eric Hosmer chased starter Chris Tillman with a run-scoring single, Moustakas drove in a pair of runs with a single off Matusz (1-4). Salvador Perez greeted Chaz Roe with an opposite-field, two-run single to right.
The Royals pulled away with a five-run the seventh. The big blow was delivered by Moustakas, who drove an 0-2 pitch from T.J. McFarland over the right-field wall after an intentional walk to Kendrys Morales filled the bases.
"At 0-2, you don't want to throw a hanging slider down the middle," McFarland said. "That's not your goal in that situation. You're trying to throw something in the dirt and try to get him to chase something and I left it up."
After Nolan Reimold got Baltimore to 11-6 with a two-run drive in the eighth, Moustakas connected off Steve Johnson in the ninth.
The previous team record for RBIs in a game was seven, by Billy Butler against Philadelphia on April 7, 2013.
"The guys got on base today, gave me opportunities to drive in some runs," Moustakas said. "I was able to capitalize on that."
Orioles shortstop J.J. Hardy said: "What did he have, seven RBIs? Nine? That's a pretty good month -- or week. What did we score? Not enough."
Baltimore has 21 games left to close a significant gap in the hunt for the second AL wild card.
Perez had two hits and three RBIs for the AL Central leaders, who won for only the second time in eight games.
Yordano Ventura (11-8) allowed four runs and eight hits in 5 2-3 innings for Kansas City. The right-hander is 7-1 in his last 10 starts, including a pair of wins over Baltimore.
The start of the game was delayed by rain for 3 hours, 2 minutes. Dark clouds hovered into the late evening and there were some rainy stretches, but no further stoppages.
Baltimore used a sacrifice fly by Gerardo Parra and a three-run shot by Adam Jones to build a 4-1 lead after three innings.
Royals: Reliever Wade Davis returned to action after being rested with shoulder soreness.
Orioles: C Matt Wieters was back in the starting lineup after missing three games with a sore left wrist. ... The Orioles hope RHP Miguel Gonzalez (right shoulder tendinitis) can come off the DL before the season ends. "Best scenario, he gets some starts," Showalter said. "It would certainly help his frame of mind."
Royals: RHP Johnny Cueto attempts to snap a four-game losing streak in the series finale Sunday night. He's 2-5 with a 4.86 ERA in eight starts with Kansas City.
Orioles: Wei-Yin Chen beat the Royals on Aug. 26 and tries for an encore. The Taiwanese left-hander is 4-1 in his last nine starts.