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The Arizona Diamondbacks gave Ian Kennedy a little lead to work with early, then sent him away with a rousing blowout victory in front of a big, happy home-opening crowd.

The right-hander struck out nine in eight dominant innings and Arizona hit three late-inning homers in the Diamondbacks' 13-2 rout of the Cincinnati Reds on Friday night.

"They won't all be this easy," a smiling Arizona manager Kirk Gibson said.

Justin Upton homered, drove in two runs and scored three times in the Diamondbacks' highest-scoring home opener since the franchise was born in 1998. Kelly Johnson had a three-run home run and Chris Young a solo shot for Arizona. All three home runs came off reliever Matt Maloney.

Xavier Nady doubled in two runs off lefty Travis Wood (1-1). Arizona's Miguel Montero was 3 for 3, two of them doubles, to boost his batting average to .545 (12 for 22).

"I was missing with some pitches and they made me pay for it," Wood said. "After the first two (innings) I kind of settled down a little bit but I was still missing. I was able to just get a little bit better but it eventually caught up to me. ... They hit the ball all over the place."

Kennedy (1-0), who had no decision as the opening-day starter in Arizona's 7-6 win at Colorado a week earlier, allowed six hits and walked one against the powerful Reds batting order.

"Ian was dealing it, man," his catcher Montero said. "He was throwing all kinds of pitches and he was throwing them for a strike. He was on, man, he was on."

Kennedy gave Montero much of the credit, saying he shook off the pitches maybe twice the entire night.

"I was throwing a lot of strikes with my off-speed pitches. When you have that, you keep hitters off balance, you have success. The offense put me ahead early and allowed me to pitch with more comfort than a 0-0 ball game. We just came out swinging and it was real exciting."

Wood allowed six runs on six hits in five-plus innings as the Reds, in their first game away from home, lost their second straight after starting the season 5-0.

Stephen Drew, in his first time in the lineup this season after being sidelined with a lower abdominal strain, doubled in one of Arizona's two first-inning runs. Upton singled in the other. After Montero's leadoff double in the second and a sacrifice bunt by Kennedy, Arizona's third run came home on Wood's wild pitch.

The Reds got a run in the third on singles by Paul Janish and Drew Stubbs, followed by Brandon Phillips' RBI sacrifice fly.

It stayed 3-1 until the Diamondbacks broke it open in the sixth. Upton walked on four pitches, Young singled, then Drew walked to load the bases with no outs. Nady lashed a double to left to bring in two runs and Wood's night was over. Things just got worse for the Reds after that.

Willie Bloomquist, moved from shortstop to left field when Drew returned, was 2 for 5 with a double and scored twice.

After Upton's solo homer in the seventh, Arizona scored six times in the eighth. Three came on Johnson's home run to right. Montero had an RBI double, Bloomquist a run-scoring single and Young a solo homer in the frame.

"It was a great atmosphere," Gibson said. "You wish they could all be this way but it doesn't happen. We know we're in for a big fight tomorrow. That's a very good team that we're playing against, well coached, and I'm sure they're highly motivated for a rematch tomorrow."

NOTES: Arizona has won five straight home openers. ... Attendance was announced as 48,027 and a sellout, although there were plenty of empty seats in the ballpark. The media guide lists capacity at 48,633. ... Roland Hemond, special assistant to the Diamondbacks president, threw out the first pitch. Hemond, a longtime executive in the majors, recently was named the second winner of the Buck O'Neil Award for his contributions to the game by the National Baseball Hall of Fame and Museum. O'Neil was the first to win it. ... Reds manager Dusty Baker still needs two wins to become the 11th manager in major league history to have at least 250 wins with each of three teams. ... Baker noted it was a quick return to Arizona, where the Reds held their spring training in the Phoenix suburb of Goodyear for the second year in a row after 63 springs in Florida.