The Arizona Diamondbacks' historic season-opening win streak over the San Francisco Giants may have come to an end on Wednesday night, but it was still a third straight series victory over their NL West rivals.The Diamondbacks, coming off an ugly sweep by the Rays, needed a boost, and the struggling Giants offered them such an opportunity.Here's what we learned from the D-backs' latest series victory, and the big question that now looms. What we learned from Diamondbacks' series win over GiantsBig bats heating upJun 30, 2026; Phoenix, Arizona, USA; Arizona Diamondbacks second baseman Ketel Marte celebrates after hitting a solo home run in the sixth inning against the San Francisco Giants at Chase Field. Mandatory Credit: Mark J. Rebilas-Imagn Images | IMAGN IMAGES via Reuters ConnectThe Diamondbacks offense, which has been struggling this season, got some sturdy contributions from some of the critical bats in the order. Ketel Marte stayed hot, going 5-for-12 in the series, including two home runs in games one and two. That set a career high of four straight games with a home run, and contributed to two strong offensive showings in Arizona's wins.Similarly, the slumping Lourdes Gurriel Jr. might be on his way out of his slump. Gurriel crushed a three-run homer to set the tone for a rout in game two, and collected three hits in games one and two combined. Over his last seven games, Gurriel is hitting to an .817 OPS. If this is the beginning of one of his patented hot streaks, the Diamondbacks' offense could be in good shape moving forward. Brandon Pfaadt is backJun 30, 2026; Phoenix, Arizona, USA; Arizona Diamondbacks pitcher Brandon Pfaadt prior to the game against the San Francisco Giants at Chase Field. Mandatory Credit: Mark J. Rebilas-Imagn Images | IMAGN IMAGES via Reuters ConnectBrandon Pfaadt, forced back into the starting rotation as a result of multiple injuries, made an excellent start in his return debut. Pfaadt looked much more in command of a game than he has all season. He limited hard contact, with just four hard-hit balls in 5.1 innings of one-run baseball. He'll need to sustain this moving forward, but it was a very encouraging sign to see the right-hander perform well, even against a struggling Giants club. Arizona may end up having to lean on Pfaadt heavily this season.Eduardo Rodriguez is D-backs' most valuable pitcherJun 29, 2026; Phoenix, Arizona, USA; Arizona Diamondbacks pitcher Eduardo Rodriguez (57) throws against the San Francisco Giants in the first inning at Chase Field. Mandatory Credit: Rick Scuteri-Imagn Images | IMAGN IMAGES via Reuters ConnectFor what felt like the hundredth time this season, left-hander Eduardo Rodriguez played stopper in a desperate moment. Rodriguez went seven strong innings, allowing just one earned run to help the D-backs claim a victory in game one. His ERA is down to 2.21, and he's continuing to create an ironclad All-Star case with each passing start.Big question after D-backs' series win over GiantsHow can the D-backs turn this into success vs quality opponents?Jun 21, 2026; Phoenix, Arizona, USA; Arizona Diamondbacks outfielder Corbin Carroll against the Minnesota Twins at Chase Field. Mandatory Credit: Mark J. Rebilas-Imagn Images | IMAGN IMAGES via Reuters ConnectBeating any major league team is difficult. But the Diamondbacks have had the Giants' number all season, and San Francisco has not had much overall success. Arizona needs to find a way to turn this success into success against tougher opponents if they want to have any chance at making the postseason. The Diamondbacks are 13-3 against the Giants and Colorado Rockies this year. Which means they're 30-40 against everyone else.Clearly, Arizona is a class above the bottom-feeding clubs, and that is step one of contention. There's nothing wrong with taking care of business. But, eventually, they'll have to build some hot streaks against tough opponents, especially with the Brewers, Dodgers and Padres looming in the schedule.Add us as a preferred source on GoogleFollow