The Valkyries have a real WNBA championship window. It starts now

Valkyries forward Gabby Williams celebrates a 3-point basket to take a 73-72 lead during the fourth quarter Thursday against the Sparks at Crypto.com Arena in Los Angeles.  (Katelyn Mulcahy/Getty Images) The Golden State Valkyries have raised the bar ever since they came into existence.

dir="ltr">Can they raise it to the ultimate height? Can they win a WNBA championship in only their second season?

dir="ltr">Improbable but certainly not impossible. As the Valkyries start their second postseason run - becoming the first team in league history to make the postseason in each of its first two seasons - they enter a wide-open playoff field, perhaps the most competitive in the league's 30-year history.

dir="ltr">From the top-seeded Lynx, who are great but not unbeatable, to the No. 8-seeded Liberty, who are erratic but loaded, multiple teams have legitimate paths to a title. That includes the Valkyries who, despite their stumble to the finish line, clinched the No. 2 seed in a wild finish Thursday night. They will open their postseason on Sunday night at Chase Center against the Dallas Wings, a team they swept 3-0 in the regular season.

dir="ltr">Sunday will be the first playoff game at Chase, as the team was forced to relocate to SAP Center last postseason due to the Laver Cup being held at Chase. Ballhalla proved it could travel, but Sunday will be something much more special: a sold-out, rocking home atmosphere. And a statement to the rest of the league.

dir="ltr">As the No. 2 seed, the Valkyries will have home-court advantage in the first two rounds, so while it may be the first playoff game at Chase, no one expects it to be the last.

dir="ltr">No opponent will be excited to face the Valkyries in their frenzied home arena. Or go against the best defensive team in the league, which plays a suffocating style. Or match wits with a team with such a clever head coach: Natalie Nakase may be the Coach of the Year for a second consecutive year. Or take on a team fully embracing the "strength in numbers" philosophy that seems to be part of the Golden State DNA, with the best bench in the league.

dir="ltr">Even the problems that surfaced in the past erratic week may work to the Valkyries' advantage in the postseason. They haven't faced much adversity recently, but they got some serious challenges in the final days of the regular season.

dir="ltr">On Tuesday in Portland, after leaping out to a 17-0 lead, and knowing they had a chance to grab the No. 1 seed thanks to the Fever's victory over the Lynx, the Valkyries collapsed. It was their worst loss of the season, and odd to see how disorganized and lackluster they seemed down the stretch.

dir="ltr">But it was perfect for Nakase, who could use the next two days to dig into the film and tell her team some hard truths. She said Portland had "exposed" her team. Veronica Burton called it a "wake-up call."

dir="ltr">"If we play like this we're going to be out quickly," Burton said. "We need to understand the sense of urgency we need to be playing every single game with."

dir="ltr">But the Valkyries didn't look like they had learned much on Thursday night in an emotional game in Los Angeles, when the Sparks were determined to send retiring forward Nneka Ogwumike out with a win.

dir="ltr">The Valkyries fell behind by 16, looking disorganized and out of sync. They were facing the real possibility of slipping to the No. 3 seed, which would put them in a first-round matchup with the Fever, not only the best offensive team in the league, but one that brings the Caitlin Clark/Sophie Cunningham circus and all that goes along with that. Best to avoid that trap in the first round.

dir="ltr">But the Chenergizer Bunny, Kaitlyn Chen, and Burton turned up the energy in the second half. And when it was crunch time at the very end, Gabby Williams played the way the Valkyries expected her to when they made her their marquee free-agent signing. She made key clutch plays, in the final minute and a half, with a 3-pointer, a steal, a layup and another 3-pointer that gave the Valkyries the lead.

dir="ltr">"Gabby's our closer," Nakase said. "I thought we even got closer (tonight). We talked about being in pressure together."

dir="ltr">In some ways, it was almost the perfect launching point and confidence boost to head into the postseason, where the Valkyries expect to last much longer than last season's quick 0-and-2-and-out experience.

dir="ltr">"That was huge," Burton said, after the game. "A whole team effort. The gutty type of win we're going to need going into the playoffs."

dir="ltr">The Valkyries still face questions. Can they produce enough offense at key moments? Can Williams be that go-to scoring threat they need? So far the Valkyries have passed every test they've faced.

dir="ltr">And as they head into their second playoff run, it's not insane to wonder: Can they pass the biggest test of all?

SubscribeThere’s more to San Francisco with the Chronicle. Subscribe today for just 25¢.This article originally published at The Valkyries have a real WNBA championship window. It starts now.