ST. LOUIS -- If this was Joe Kelly's last turn, he's leaving with his head held high.

The rookie right-hander pitched into the seventh inning of what could be his final start before Jaime Garcia comes off the disabled list, and the St. Louis Cardinals got home runs from Matt Holliday and Jon Jay in an 8-2 victory over the Arizona Diamondbacks on Tuesday night.

"I love him in the rotation," second baseman Skip Schumaker said after getting two hits and turning a dazzling double play to his left on a short hop to rob Miguel Montero in the second. "I don't obviously manage but he's making it really difficult on everyone to move him out.

"We think the world of him."

Montero hit a two-run homer for the Diamondbacks, who have lost four of six to drop to .500. They are 0-4 against the Cardinals this season.

Ian Kennedy (10-10) made throwing errors on consecutive sacrifice bunt attempts to help the Cardinals score two unearned runs in the seventh for a three-run cushion, and gave up both homers for a four-game total of eight long balls.

"I feel like the two of them were good pitches, but obviously not good enough," Kennedy said. "It's frustrating when you give up those solo home runs.

"Every once in a while, they add up."

Kelly (3-5) gave up two runs in 6 1/3 innings and matched his career best with six strikeouts, lowering his ERA to 3.41 -- trailing only Kyle Lohse's 2.72 in the rotation. Garcia had eight strikeouts and three walks, throwing 93 pitches in five innings for Triple-A Memphis in his fourth rehab start Tuesday night.

Manager Mike Matheny swatted away a question about whether Garcia was ready to step in, saying "too early for that right now." Before the game he said he advised Kelly to ignore speculation.

"Everyone else thinks about it a lot more than I do," Kelly said. "It hasn't really crossed my mind. Until someone tells me otherwise, I'll just keep the same routine, same plan."

Holliday's two-run homer in the fourth reached the third deck in left just inside the foul pole to put St. Louis ahead. His 23rd homer topped last year's total.

Jay hit his fourth of the year to open the sixth for a 3-0 lead.

Kelly had cruised through the middle innings Justin Upton singled to start the seventh. Montero homered to straightaway center on the next pitch, his 14th of the season.

In minutes, Kennedy doubled his season total of two errors through his first 23 starts and helped the Cardinals pull away. He was off-balance fielding Rafael Furcal's sacrifice bunt and double-pumped an underhand throw that first baseman Paul Goldschmidt dropped after being screened to put two men on with none out in the seventh.

Kennedy then floated a throw high over third base on what would have been an easy forceout on pinch hitter Shane Robinson's sacrifice attempt to allow a run.

"We just self-disintegrated at the end of the game," manager Kirk Gibson said. "We made two errors on two trivial bunt plays."

Kennedy entered the season with three career errors in 100 starts. He's 1-3 with a 8.59 ERA against the Cardinals in four career outings.

Allen Craig added a run-scoring groundout with the bases loaded off Brad Ziegler to make it 5-2 in the seventh. Pinch hitter Matt Carpenter was credited with a two-run double on a low liner that center fielder Gerardo Parra trapped and then tried to sell as a catch as the Diamondbacks began trotting off the field. Second base umpire Gary Darling, closest to the play, reversed third base umpire Paul Emmel's call as the Cardinals kept running.

"I had a great view of it. I knew it was down," Carpenter said. "You would have thought he for-sure caught it, the way he was acting."

Kelly survived a pair of fielding miscues by Holliday and Jay in the first and third to keep it scoreless.

Holliday froze in his tracks in left and retreated too late on Jason Kubel's double that bounced off the warning track with two outs in the first, but Kelly struck out Goldschmidt. Jay broke in from center on Stephen Drew's one-out triple in the third and with a late dive got just the tip of his glove on the ball, but Kubel grounded into a double play.

Jay made a nice juggling catch at the wall to rob Drew for the last out in the fifth. The ball squirted out of Jay's glove as he hit the ball but he re-gloved it while landing.

Notes

• Carpenter is 7 for 24 as a pinch hitter with 10 RBI, most by a Cardinals rookie since Joe Frazier had 15 in 1954.
• The Cardinals have won six in a row in the series dating to last season.
• Kennedy has surrendered 23 homers, among the league leaders.
• Montero leads all catchers with 70 RBI.
• Adam Wainwright (10-10) is 4-0 with a 1.53 ERA in his last four home starts entering Wednesday night's matchup against Joe Saunders (6-8, 3.53). Saunders allowed six earned runs in 3 1/3 innings in a loss to St. Louis on May 7.
• Carlos Beltran was 6 for 17 with two homers and six RBIs against Kennedy before striking out all three at-bats.