The Padres and D-backs square off seven times in their next 11 games, starting with a four-game set at Chase Field on Thursday.
The D-backs have won 12 of their last 14 games entering Wednesday and have stretched their lead over the second-place Giants to seven games. They are 7-4 against the Padres this season, including a three-game sweep at home from Aug. 26-28.
San Diego is 19 1/2 games behind Arizona in the standings, but the Padres aren't going to lay down for the rest of the season.
"The bottom line is we've got to keep fighting," San Diego outfielder Cameron Maybin said. "We've got to make these teams beat us -- I still think we can do some special thing."
If Arizona can hang on down the stretch, the D-Backs could make their first playoff appearance since 2007.
"It's nice that guys are recognizing the importance of these games now, what it means to our division race and stuff like that," Arizona veteran infielder Geoff Blum said. "So I think everyone has responded pretty good and is having a good time doing it."
Padres: Forsythe done
San Diego rookie third baseman Logan Forsythe is done for the season.
Forsythe hasn't played since Aug. 31 due to a sore right knee, but now is having problems with his left knee, which was surgically repaired last year. He will have the same meniscus surgery on the knee Friday.
The rookie had been filling in ably for Chase Headley.
"The stints he was here, we saw growth," manager Bud Black said. "His at-bats got better, his defense got better. He wasn't as wide-eyed. He was playing in a state of relaxed confidence."
D-backs: Arizona bats streaking
The D-backs could have three hitters carrying at least seven-game hitting streaks into Thursday's game. Entering Wednesday's action, Willie Bloomquist had hit safely in seven straight games and gone 11-for-28. Aaron Hill extended his hitting streak to 10 games with a third-inning single Wednesday,; he entered the game 18-for-35 during the previous nine games with just one strikeout.
Leading the team is catcher Miguel Montero, whose 15-game hitting streak is the longest by a catcher this season. Montero was 19-for-54 with 13 RBIs during his streak entering Wednesday; he belted a two-run homer in the third inning to continue the streak.
San Diego's starter for the series opener, Cory Luebke, is 0-2 with a 6.57 ERA against Arizona this season in four games, including two starts. In 6 1/3 innings at Chase Field, he allowed five earned runs and is 0-1.
Arizona ace Ian Kennedy starts for the D-backs in the opener. He's 2-0 with a 2.08 ERA against San Diego in 2011 and 4-0 in his career against the Padres. San Diego hitters are batting just .200 against Kennedy in two starts this season and have struck out 16 times against just one walk.