Holton-Arms pulled off an upset over St. Stephen’s/St. Agnes in the ISL AA semifinals. (Toni L. Sandys/The Washington Post)

Holton-Arms Coach Janet McCormick has spent the past few days texting, calling and emailing as many Panthers alumni as she can. She has a question that past schedules, records and team archives aren’t helping answer.

Before Saturday in the Independent School League AA semifinals, when was the last time Holton-Arms beat St. Stephen’s/St. Agnes?

“We can’t find a time that Holton has ever beaten Saints” McCormick said. “Maybe, but not as far back as anyone I can find to remember. This was monumental for our school.”

The Saints had won at least the last 21 ISL AA tournament championships — as far back as league records are kept — but the Panthers, who finished as the conference No. 4 seed in the regular season, never trailed in the semifinal and won, 10-9.

It advanced Holton-Arms to the championship against Georgetown Visitation, which started Monday before officials postponed the game at halftime until Wednesday because of severe weather warnings. Though the Panthers will restart the contest trailing 9-3 with 25 minutes to play, McCormick wants her  players appreciate the significance of their finish.

“I was like, ‘You guys already did the hard part. History is made one way or the other,’ ” McCormick said. “Now just finish it and make it your own.”

McCormick believed her squad could manage a playoff upset after Holton-Arms lost to St. Stephen’s/St. Agnes in the regular season. Half the Panthers, she said, entered the April 12 game believing they could win. After the three-point loss, McCormick recognized a confidence boost among the rest.

Midfielder Stephanie Hong scored the eventual game-winning goal to ensure the league will crown a new champion.

“They’ve certainly earned that respect, for sure,” McCormick said of the Saints operating as a league dynasty. “It really makes it that much sweeter to be the first ones to do it.”

McCormick also marveled that in addition to her squad downing a longtime power, Notre Dame Prep beat McDonogh, a nationally dominant program in Baltimore, on the same weekend to break McDonogh’s record 198-game winning streak.

“That’s its own story,” McCormick said. “In the same weekend, that’s ridiculous.”

Here are this week’s rankings.

1. Glenelg (14-2) Last week: 2

For a third straight year, Glenelg defeated Marriotts Ridge in the Maryland 2A South region semifinal.

2. Bishop Ireton (18-3) LW: 3

Having beaten St. Stephen’s/St. Agnes in overtime for the Virginia Independent Schools Athletic Association championship last year, the Cardinals will start their quest for a repeat this week.

3. Georgetown Visitation (16-2) LW: 5

The Cubs started the ISL AA championship on a 6-0 run and will return to the final, up 9-3, on Wednesday against Holton-Arms.

4. St. Stephen’s/St. Agnes (24-3) LW: 1

After their first ISL AA tournament lost on record, the Saints enter this week’s VISAA tournament as the No. 1 seed.

5. Marriotts Ridge (12-3) LW: 4

In a an early playoff meeting between two of the best teams in the state, the Mustangs fell, 12-11, to Glenelg on Monday.

6. South River (15-2) LW: 6

The Seahawks downed Broadneck, 15-11, on Monday to set up an Anne Arundel County championship rematch against Severna Park in the 4A East region final.

7. Holton-Arms (15-5) LW: NR

Stephanie Hong, who had the deciding score against St. Stephen’s/St. Agnes, leads the Panthers with 60 goals this season.

8. Langley (12-1-1) LW: 8

The Saxons defeated Herndon, 22-8, to advance to the Liberty District championship against McLean on Tuesday.

9. Dominion (14-0) LW: 10

The Titans downed George Mason, 12-7, on Friday to finish the regular season undefeated and win their first Dulles District title.

10. Glenelg Country (12-5) LW: 7

The Dragons ended their season with a 7-5 loss to Notre Dame Prep in the IAAM A tournament semifinals.

Dropped out: No. 9. George Mason (11-2)

Bubble: W.T. Woodson (12-3), Severna Park (11-5), Whitman (12-1), George Mason (11-2)