Zack Greinke held Kansas City scoreless through 8 1/3 innings before he was replaced by Ernesto Frieri, who gave up back-to-back homers as the Royals pulled out a 3-2 walk-off victory in the ninth inning.
Despite the loss, the Angels remained 2 1/2 games behind the Orioles -- who dropped a 5-2 decision to the A's on Saturday -- for the second American League Wild Card spot.
In Sunday's rubber match, Dan Haren (10-11, 4.45 ERA) will start for the Halos. It's been a tough season for the 31-year-old. If the season ended today, Haren's ERA would be his highest as a full-time starter since his rookie year (5.08) and he'd also have more losses than wins for the first time since going 3-7 in 2003.
However, Haren has been much better as of late and appears well on his way to concluding the 2012 campaign on a high note. He's allowed a total of six earned runs in his past 25 innings (four starts) and is 2-1.
That one loss came in his last outing, as Haren gave up four hits and three runs in 6 1/3 innings to the A's. However, two of them went for home runs in the Angels' 3-1 loss.
The Royals will counter with rookie left-hander Will Smith, who is 5-7 with a 4.94 ERA through his first 13 starts. Smith squared off against the Halos on July 24, when he yielded two hits and one run in seven innings while striking out four.
The only outing that compares is Smith's latest. The 23-year-old tossed seven scoreless innings against the Twins on Tuesday.
"I didn't have a 1-2-3 innings the whole time and you'd like to clean that up. But it's a big confidence boost," Smith said.
Angels: Rotation vs. Rangers excludes Big E
With a crucial three-game set upcoming against the Rangers, manager Mike Scioscia announced that his rotation would go Jered Weaver on Tuesday, C.J. Wilson on Wednesday and Greinke on Thursday. It was supposed to begin with Ervin Santana, however, he is still recovering from a line drive off his forearm in his last start.
"Ervin just got smoked on the forearm, with which you might want to take a couple more days. You might want to take advantage of that," Scioscia said.
Scioscia didn't announce when Santana's next start would be, but said it would come sometime during the series against the White Sox next weekend.
"[It's] some setback a little bit, as far as when he's going to throw his 'pen and everything, but that's not the determining factor," Scioscia said.
Mark Trumbo and Torii Hunter are the lone Halos with hits off Smith in that July outing. Trumbo was 1-for-3 with the only RBI.
Royals: Injuries will factor into 2013 plans
Lorenzo Cain, Jarrod Dyson and Chris Getz have sustained multiple injuries this season and for manager Ned Yost, those injuries will be noted when he goes to assemble a 25-man roster next season.
"Absolutely it [factors in]," Yost said. "You better have guys on your roster that are durable and guys that can make it through a 162-game season. ... When you get to a point where you're competing, you want your best players on the field, you want them to be able to play through stuff."
Billy Butler is 5-for-15 (.333) vs. Haren in his career with one extra-base hit. Alex Gordon, however, does not have the same luck as he is 2-for-11 (.182).
The Angels have 16 games remaining as they try to clinch a Wild Card spot. However, nine of those are against the White Sox and Rangers, both first-place teams in their respective divisions.
Haren is 3-0 with a 1.80 ERA in five career starts at Kauffman Stadium.