SAN FRANCISCO -- In his own way, Giants left-hander Madison Bumgarner -- a 22-year-old man of few words -- may have best summed up the magnitude of this weekend's National League West showdown between the division-leading D-backs and his second-place club.

"The rest of the season has a lot to do with these next few games," Bumgarner said.

That holds true for both teams, separated by a six-game margin as they prepare to kick off a critical three-game series at AT&T Park on Friday at 7:15 p.m. PT. The two are also scheduled to meet later this month, but this series could determine the way each club approaches the rest of September, setting up that Sept. 23-25 series as either a final slugfest for first place or an inconsequential late-September series between a contender and an also-ran.

For the D-backs, who enter having won nine straight, a convincing series victory would all but guarantee a playoff spot, extending their division lead and allowing them to ease into the postseason instead of using their remaining energy and risking injuries just trying to claim the NL West crown. It would lengthen their torrid nine-game winning streak. And it would give them a chance to keep players fresh, all the while, of course, removing an enormous burden from their shoulders.

But if they fall, the pressure is at least somewhat back on the D-backs. Their comfortable division lead will begin to look smaller and smaller. The worry would sneak back into their minds that the defending World Series champions have not yet given up on the season, and Arizona has to play as hot as it has been to stay on top of the division.

"It's a really important series, because any time you can play the team that's behind you in the division in September is huge," said Arizona right-hander Daniel Hudson, who will start Sunday's series finale. "You see how momentum can change in this game really quick. If we can take that momentum with us into that series and kind of put a little bit extra distance between us and get a little extra cushion, that would be a big help."

For the Giants, two or three wins could be enough to pull them out of the considerable hole they've dug due to their lethargic offense. A series win could energize the weary, injury-riddled lineup and finally reward the hard-luck pitching staff for its efforts all season, putting the defending champs in position to make another magical ride through September and, once again, into October.

Two or three losses, on the other hand, and the Giants might start looking toward next year. The Trade Deadline deal for Carlos Beltran, which cost San Francisco pitching prospect Zack Wheeler, would begin to look less savvy than it did at the time. Veterans would start losing playing time to prospects like Brandon Belt, Brandon Crawford and Brett Pill. Arguably the top pitching staff in baseball would see its outstanding year go to waste. The Giants would hate to see their once-inevitable playoff berth claimed by a younger, hungrier club.

Make or break? Absolutely.

"I don't see how it couldn't be," said Giants outfielder Pat Burrell, who's expected to start in left field on Friday after coming off the disabled list on Wednesday. "There's no secret these guys are coming in [hot]. They've proven that they deserve to be where they're at, and we've slipped -- no doubt about it. But it isn't over. We're going to fight this thing out. The better team is going to prevail, obviously, and obviously we feel like we are that team."

The Giants certainly have enough quality pitching to believe that, and they will put their best arms on full display this weekend, with right-handers Matt Cain, Tim Lincecum and Ryan Vogelsong taking the mound. But the D-backs will trot out a formidable staff of their own: lefty Joe Saunders on Friday, dominant right-hander Ian Kennedy on Saturday and Hudson on Sunday.

"It's going to be exciting because you've got Joe, me and Huddy going, and they've got their three best going," said Kennedy, who will carry a 17-4 record and 3.03 ERA to AT&T Park.

There is no doubt that, on paper, the Giants hold the edge in the pitching department. But where they lag behind in the arms race, the D-backs own a noticeable edge at the plate and in another more unexpected area: They have the upper hand this time around.


"I don't feel like we're out of it. ... We've got to push them."
-- Giants infielder Mark DeRosa

The Giants started off the clubs' Aug. 1-3 series in control of their own destiny and seemingly a lock for the postseason, having recently taken two of three in Philadelphia and picked up Beltran. Then, the D-backs came to San Francisco and took two of three behind Kennedy and Hudson, sending the Giants into a month-long tailspin.

"I know there's going to be a little more of an adrenaline rush with a playoff-type atmosphere," Kennedy said. "The beginning of the year, even here, they were just kicking our butts. It gives us confidence that we played well there because they've got the sold-out crowds, the fans behind them, and if you beat anyone of that caliber at their own field, it gives you more confidence going into the series, for sure."

But the Giants aren't quite so ready to give away the high ground.

"I don't feel like we're out of it -- we control our own destiny, to a certain degree," Giants infielder Mark DeRosa said. "If we play well against Arizona to start the month off, then we know that we're not going anywhere, then they're going to have to play good baseball. We won the World Series last year. They have a lot of young guys over there. We've got to push them."

Unfortunately for the Giants, one of those young guys is Justin Upton, putting together a year worthy of NL Most Valuable Player Award consideration. The 24-year-old right fielder is batting .294 with a .909 on-base plus slugging percentage, 36 doubles, 26 homers, 20 stolen bases and 80 RBIs.

And as center fielder Chris Young said, the D-backs' youth might actually help them stay focused and comfortable, as they have done all season, instead of causing them to tighten up and think too much about making each series a chance to throw a knockout punch.

"The last thing we want to do is put too much pressure on ourselves for any games coming up," Young said. "We've been able to play loose all season. I think the main focus is to continue to be able to play loose and continue to do what you're doing and not change your plan or do what you haven't been doing, because it's getting down to the wire."

But what Arizona brings in youth and enthusiasm, the Giants match in experience and desire. They weren't in much better shape last Sept. 1, eventually rallying past the crashing Padres to claim the NL West crown en route to a World Series title. And they aren't about to step aside and let their title defense end in the first weekend of September.

"We're going to fight until the end," Giants catcher Chris Stewart said. "Until we're absolutely eliminated, we're not going to give up. It's just not in us. It's been a rough go-round, but we're not going to give up. We're going to go out and play hard every night and hopefully come away with some wins."

Just as Bumgarner simply stated the significance of the series, so, too, did D-backs catcher Miguel Montero, who simply expressed what to expect as part of the NL's closest division race.

"It's going to be a fun one," Montero said. "We're just going to go out there and keep doing our thing and keep playing the game hard, and things will take care of themselves."