• Figure this: The Devil Rays finished their 10-game road trip 1-9, and have lost 13 of their last 14.
• It was over when... The Royals busted loose for six runs in the eighth, highlighted by consecutive two-run doubles from Ross Gload and Alex Gordon, and a Pena RBI double.
• In a losing cause: Jonny Gomes had four of the Devil Rays' eight hits, including a two-run double in the eighth.
-- ESPN.com news services
Royals 12, Devil rays 4
KANSAS CITY, Mo. (AP) -- The scouting report on Tony Pena Jr. when the Royals aquired him in a spring training trade with the Braves talked about his glove, not his bat.
Maybe opposing pitchers are looking at the same report.
Pena, who played in only 40 games as a rookie last year for Atlanta, had three doubles to help send Tampa Bay to its 13th loss in 14 games. The Devil Rays finished their road trip with a 1-9 record, the worst three-city trip in franchise history.
"It is probably more than we expected," Royals manager Buddy Bell said of Pena's offense. "Tony's played great. He's been out there every day, almost every inning. He's got some big hits and made some big plays."
Pena has a seven-game hitting streak, raising his average to .281.
"I'm surpassing," Pena said of his offensive expectations. "I wasn't thinking about that much offense when I came, just catch the ball and try to put the ball in play."
De La Rosa (7-9) went 5 2/3 innings, striking out seven to match his career high. He gave up two runs and five hits with three walks, and hasn't lost since June 22 against Milwaukee. Before that, De La Rosa had not won since May 13 -- losing six times with two no decisions.
Scott Kazmir (5-6) took the loss, giving up five runs -- four earned -- and seven hits with three walks. He struck out four and lasted only five innings throwing 105 pitches, once again struggling with high pitch counts.
"Kaz just struggled again command-wise," Devil Rays manager Joe Maddon said. "We took him as deeply as we could. I did not want him to go beyond that number of pitches."
Pena's bases clearing double in the sixth off reliever Jason Hammel scored Esteban German, Alex Gordon and Jason LaRue. It was the Royals' only hit of the inning after German and LaRue walked, and Gordon reached on Brendan Harris' fielding error.
"I was seeing the ball pretty good and just being a little more patient at the plate -- getting some better pitches to hit -- and that was the key," Pena said. "I'm just trying to drive the ball where the pitches are pitched, not try to do too much with it. Good things are happening that way."
Kansas City's six-run eighth featured back-to-back two-run doubles by Ross Gload and Gordon, and Pena's RBI double.
After Kazmir exited, five Tampa Bay relievers combined to give up seven runs on five walks and seven hits in three innings.
"That's been a big problem for us," Maddon said. "If you look at our numbers, we walk too many and the batting average against us is very high. We have to stop walking people and start making some pitches and we're just not doing it.
"We just can't pitch like that and expect to compete on a nightly basis. That's just not going to happen."
Jonny Gomes doubled in the eighth, scoring Carlos Pena and Wigginton and cutting the Royals' lead to 6-4. Gomes finished with four of Tampa Bay's eight hits, and his solo homer in the sixth was his ninth home run in 42 career at-bats against the Royals.
Royals OF Mark Teahen struck out twice and has struck out in 20 consecutive games. He stranded five runners on base. ... OF Carl Crawford was held out of the Devil Rays lineup. Maddon said he wanted to give Crawford a rest before going to the All-Star game in San Francisco. Crawford did fly out as a pinch hitter in the eighth. ... Kansas City rookie DH Billy Butler batted third for the first time. He went 1-for-3 with two walks.