San Diego State had its largest women’s volleyball crowd of the season Saturday afternoon at Peterson Gym — some to see the Aztecs take a step closer to a berth in the Mountain West Tournament, some for a volleyball alumni reunion that this year honored former coach Mark Warner, some for the free license plate frame giveaway.

And some, no doubt, for the curiosity surrounding San Jose State’s team that is said to include a transgender athlete.

The Aztecs won 3-1 (25-18, 25-22, 23-25, 25-19) to move into a three-way tie for third place at 9-5 with four matches remaining. The top six teams qualify for the conference tournament in Las Vegas over Thanksgiving week, and the top two receive first-round byes.

The Aztecs didn’t mathematically secure a spot in the tournament; one more win will do it.

San Jose State did, however, with its 11-5 record.

The twist: The Spartans are only 5-5 on the court but have received six forfeit wins from Mountain West teams refusing to play them, presumably in protest of facing senior outside hitter Blaire Fleming, who has been identified as transgender in a federal lawsuit contesting the NCAA’s policy for transgender athletes in women’s sports.

The even bigger twist: Her teammate, senior setter Brooke Slusser, joined the lawsuit and has been outspoken that Fleming should not be allowed to play.

The match featured metal detectors outside Peterson Gym, additional security and police officers stationed behind each bench.

The cheering consisted mostly of “Let’s go, Aztecs” until the third set, when a group of about 15 people sitting near the top of Peterson Gym unfurled a “Save Women’s Sports” banner and began chanting, “No men in women’s sports.”

The chanting increased in frequency and volume, particularly when Fleming was serving, until Dave Noll, SDSU’s associate athletic director for operations and events, climbed into the stands and spoke with them.

It was preceded by the public address announcer reading the Mountain West’s fan conduct policy asking “all persons to please show respect for the opposing team, game officials and each other” while warning that any acts “in conflict with good sportsmanship, safety and fair play are subject to ejection and prosecution.”

The interaction between Noll and Patrick Higuera, a fan from Oceanside wearing a white T-shirt with two pink Xs, grew heated and drew the presence of four police officers in the aisles. An SDSU fan briefly intervened in defense of Noll before police stepped between them.

Noll left after several minutes, and the group stopped chanting.

SDSU officials declined to comment on the incident. Neither team made players or coaches available afterward.

“He came up there and he was trying to tell us, oh, you’re breaking Mountain West rules because you’re pointing out a certain individual,” said Higuera, who was accompanied by his wife, Rosie, an SDSU alum who recently was defeated for a seat on the Oceanside Unified School District board. “I said, ‘You’re full of crap and you’re a coward because you don’t stand up for women’s rights.’ How dare you let a guy on an opposing team play in women’s sports.”

The Mountain West’s game handbook states:

“In the event of direct comments to a player, which include profanity or a ‘personalized’ verbal attack on that player, match management personnel or institutional administrators shall confront the individual(s) and ask for their cooperation. If the behavior continues, the individual(s) shall be asked to leave.”

It’s a tricky subject, because Fleming and San Jose State, bound by student privacy laws, have never officially confirmed the player’s gender history. Slusser did in the federal lawsuit, and associate head coach Melissa Batie-Smoose reportedly did in a Title IX complaint filed with the university claiming it has violated the Title IX rights of the team’s other 18 players through preferential treatment toward Fleming.

Batie-Smoose was suspended indefinitely by the university last weekend for undisclosed reasons and did not accompany the Spartans on the road trip.

Slusser and Fleming are both starters and arguably the Spartans’ best players, but they noticeably had little interaction in a sport known for its connectivity, with huddles, hugs and high-fives after almost every point.

The two did not slap hands during pregame introductions or on the floor after points. During one timeout, Spartans players formed a circle with arms over each other’s shoulders; Slusser and Fleming happened to be standing next to each other, but there was a gap between them with no physical contact, breaking the circle.

Fleming finished with 15 kills, and Slusser had 27 assists — both highs for either team. But it wasn’t enough to thwart the Aztecs, who got 14 kills from Taylor Underwood, 20 assists from setter Andrea Campos, 24 digs from libero Gianna Bender and three blocks from 6-foot-5 Shea Rubright.

San Jose State led 18-17 in the first set before surrendering eight straight points, including three on backline errors by Fleming as she came forward for spikes.

The Spartans led 23-22 in the second set, then lost three straight points and the set.

SDSU dropped the third set 25-23 as the incident in the stands played out, then prevailed 25-19 in the fourth despite Underwood, the NCAA leader in hitting percentage, leaving midway through the set with an ankle injury.

It gave the Aztecs a sweep of the season series after winning 3-0 in San Jose last month. If the current seedings hold, there’s a chance they could meet again in the semifinals of the conference tournament.

SDSU has four regular-season matches remaining. San Jose State has only two, against Colorado State and Fresno State. Wyoming (Nov. 14) and Boise State (Nov. 21) each forfeited their remaining matches against the Spartans.