PHOENIX -- San Diego had become Ian Kennedy's spa day in the NL West: He had never lost to the Padres in nine career starts and had seldom been in trouble, giving up just one run five times.
But in a matchup of unbeatens Saturday, Kennedy got a little beat up, and it started with the long ball, which has been his biggest challenge this season.
Kennedy, who had given up two home runs in 57 2/3 previous career innings against the Padres, gave up three bases-empty homers in five innings to fall behind, then lost the strike zone in the sixth, when he walked three and hit a batter before Yonder Alonso's two-run single knocked him out of the game.
San Diego left-hander Clayton Richard remained unbeaten in seven career starts against the D-backs in a 9-2 victory that kept the D-backs from gaining ground in the NL West or wild-card races after division leader San Francisco and No. 2 wild card St. Louis lost earlier in the day.
Justin Upton celebrated his 25th birthday with an inside-the-park home run, the first of his career, but that was all the production the D-backs (64-63) got until Aaron Hill homered with two outs in the eighth inning.
"They swung the bats well," Upton said. "Every time they came in, they hit. It's pretty tough to win like that. They did a pretty good job of staying on the gas pedal."
Of Richard, Upton said: "He's changing speeds, and for some reason he hits his spots against us."
Kennedy (11-11) has been a strong second-half pitcher in his three seasons with the D-backs, but this year has been atypical. He was 16-4 after the All-Star break in 2010-11 and is 5-4 this season, with an ERA about two points higher than the previous two years combined. He is 6-1 with a 3.00 ERA against the Padres in 10 starts.
Kennedy has given up 13 homers in nine starts since the All-Star break.
After giving up homers to Chase Headley, Carlos Quentin and Alonso that gave the Padres a 3-2 lead in the fifth, Kennedy is now tied with Dodgers right-hander Joe Blanton for the NL lead with 26 homers allowed. It is exactly as many as he gave up in 2010 and seven more than last year. Kennedy has given up 13 homers in nine starts since the All-Star break, with two three-homer starts.
"You can't talk about last year, but the year before, it's about the same," Kennedy said. "And a lot of times they come in bunches. It's part of this game.
"Part of pitching here."
Headley hit an inside fastball that he appeared to be cheating on, keeping his hands in and driving the ball down the left-field line in the first inning. Quentin and Alonso hit off-speed pitches that were high in the strike zone. When Kennedy has gotten in trouble this season, it has been when his ball has stayed up.
"The ball Headley hit was a pretty good fastball inside. He is locked in. The other ones were mistakes," D-backs manager Kirk Gibson said.
Upton's home run, his 10th, gave the D-backs a 2-1 led in the second inning. After Paul Goldschmidt walked, Upton hit a line drive off the fence near the 413-foot sign in right-center field. The ball caromed back toward left-center and past center fielder Cameron Maybin, who was coming across to help, and Upton scored easily.
He showed no signs of the tight left hamstring that forced him to leave Tuesday's game early and kept him out for the next three.
"I kind of knew it was at least a double, the way I hit it. Once I saw it ricochet off the fence, I knew I had a chance at scoring. I kind of turned it on a little bit. I got tired around third, and luckily I had time to get in," Upton said.
Kennedy threw 103 pitches in 5 1/3 innings, and leadoff man Everth Cabrera set the tone with a 10-pitch at-bat to lead off the game. The Padres, who have the best record in the NL West since June 9, saw 30 pitches in the sixth inning off Kennedy and Matt Albers.
Cabrera and Headley walked, and Kennedy then hit Quentin to load the bases with one out. Yasman Grandal drew a walk on a 3-2 changeup to force in a run, and Alonso's single to right field drove in two for a 6-2 lead.
"They are taking a lot of pitches and fouling off a lot of pitches to get deep in counts. They're doing a good job of that," Kennedy said.
