SAN FRANCISCO — Suddenly, Blake Snell is looking like one of the most fascinating players to watch in the days leading up to Tuesday’s 3 p.m. PT Trade Deadline.

The reigning National League Cy Young winner delivered one of the most dominant performances of his career in Game 1 of Saturday afternoon’s doubleheader against the Rockies at Oracle Park, striking out a personal-best 15 over six shutout innings in a 4-1 win for the Giants.

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Snell allowed only two hits — including a first-inning double to Brenton Doyle that was misplayed by center fielder Heliot Ramos — while using his electric fastball-curveball combination to induce 30 swinging strikes, the most by a Major League pitcher in a single game this year. He is the first pitcher in AL/NL history (since 1901) to rack up 15 strikeouts while only pitching six innings or fewer, and the first Giant to record a 15-strikeout game since fellow Washington native Tim Lincecum did so on this date in 2009.

Snell said he wasn’t pitching for strikeouts at the beginning of the outing, but that changed once he realized he had a chance to match or even exceed his previous career high of 13.

“I wasn’t trying early on,” Snell said. “The last couple of innings, I was really trying. I was like, ‘I need to get to 13.’ When I went out for the sixth, I was well aware of what I was trying to do.”

Snell took the mound in the sixth with 12 K’s under his belt and issued a leadoff walk to Ezequiel Tovar, but he capped his brilliant outing by punching out Brenton Doyle, Brendan Rodgers and Kris Bryant, who went down swinging on a curveball in the dirt. Snell generated 14 of his swing-and-misses on his curve, which he used 35% of the time against the Rockies.

“I’m starting to have more confidence and understanding how to make adjustments quicker now,” Snell said. “I’m getting there, as weird as that is to say. I still feel like I have more to improve on. But I would say the curveball is probably the best it’s been for a while.”

After recording a 9.51 ERA over his first six starts of the year, the 31-year-old left-hander now has a 0.75 ERA with 30 strikeouts and seven walks over 24 innings in four outings since returning from the injured list. The question now is whether he’ll spend the rest of the second half with the Giants or be one of the biggest stars dealt by Tuesday’s Deadline.

Even with Saturday’s sweep of the doubleheader, the Giants (52-55) remain three games under .500 and with slim odds of climbing back into the crowded National League Wild Card race. Given their place in the standings, it could make sense for the Giants to move Snell, who will have the ability to opt out of the final year of his two-year, $62 million contract and become a free agent at the end of the season. If Snell doesn’t opt out, he’ll be owed $30 million in 2025, with $15 million deferred to 2027.

“We’ve just got to win,” Snell said when asked about trade rumors. “If we win, I ain’t going nowhere. At least, I believe that. I don’t really know. I’ve seen crazy things happen. I don’t look into it too much. We’ve got to win.

“We’ve got really good starting pitching. That then makes our bullpen even stronger. I like where we’re at. I like the rest of the schedule, I’ve looked at that as well. I think it could be a really fun last couple of months. We’ve just got to win. As long as we can win again tonight and tomorrow, I like our chances to really push and find a way to get in.”

Snell’s resurgence, coupled with Robbie Ray’s return and Alex Cobb’s impending season debut, could compel the Giants to avoid selling and try to make a playoff push down the stretch, but the club’s bats haven’t inspired a ton of confidence that they have enough firepower to support the revamped rotation in the second half.

Matt Chapman launched a solo shot off Ryan Feltner to open the scoring in the second, but the Giants couldn’t hold the slim 1-0 lead once Snell departed after throwing a season-high 103 pitches. Ryan Walker surrendered a game-tying homer to Michael Toglia in the seventh, costing Snell a chance to collect his first win as a Giant, but San Francisco regained the lead behind Patrick Bailey’s two-run, go-ahead double off Justin Lawrence in the bottom of the seventh.