In a league such as the Washington Catholic Athletic Conference, where girls’ soccer powers are perennial, coaching tenures measured in decades, and high school matches make enemies of club team friends, rivalries fester as grudges that aren’t soon forgotten.

So after a year that saw O’Connell beat St. John’s, 6-1, in the regular season, then shut out the Cadets in a playoff game, St. John’s (4-1-3) remembered it had something to prove in Tuesday’s match.

The Cadets proved it, earning a 2-1 win in what grew into a physical, hard-fought game. Junior Karen Aye drove home the game’s first goal seconds into the second half, and after O’Connell (4-2-0) tied it, freshman Ashley Ventura set up her classmate Cassandra Fernandez for the game-winner, Fernandez’s second career goal.

“Last year, they beat us 6-1 and 4-0,” said Aye, who said she’d heard the O’Connell team laughed when it heard it was going to face her Cadets in the playoffs. “It felt good to get a win, beat them, and know who SJC is.”

“It’s O’Connell, Good Counsel, and us every year,” St. John’s Coach Devin Payton said of the annual renewal of one of the WCAC’s most heated rivalries. “Our games are battles, they’re pure wars. . . . I really appreciate the effort the kids gave today, they did the job.”

So far this season, inconsistency has plagued the Cadets, who tied top 10 teams Bishop Ireton and Churchill, but lost to Blair (2-5-0) and Paul VI (2-3-1).

“We’ve been ahead three or four times on teams, up by two goals or more, and have allowed people to come back and tie us, or even lose,” Payton said. “I think they’re learning once you’re on top of a team, you have to put them down and finish them off.”

That killer instinct will be tested in the coming weeks: the Cadets’ next game comes against No. 1 Good Counsel on Oct. 8. Last season, St. John’s gave the eventual league champions all they could handle in a 1-0 loss in the regular season finale.

“This win helps us a lot,” Aye said. “We’re ready for [Good Counsel] this year.”

Broadneck shakes up Anne Arundel County

Last year, Anne Arundel County was a two-team race between Arundel, who went undefeated during the regular season, and South River, the eventual state champions who avenged a regular season loss to the Wildcats with a win in the county championship game and again in the region finals.

But a third horse charged into the 2013 race last week when Broadneck (4-0) rallied from a two-goal deficit to beat the Seahawks 3-2.

“That was definitely one of our goals this year coming in, to beat the best teams,” Coach John Camm said. “Last year, Arundel and South River were clearly the best two teams. We got better late. . . . We felt confident we could compete with Arundel and South River, it was just a matter of stepping on the field and doing it.”

South River (5-1) handed Arundel (4-1) its only loss of the season so far, setting up the mid-October matchup between Arundel and Broadneck as an opportunity for the Bruins to stake an authoritative claim to Anne Arundel elite status.

The Post Top 10

After an undefeated season in 2012, Arundel makes its first appearance in this week’s rankings. . . . Bishop Ireton will be tested with an upcoming schedule that features No. 1 Good Counsel and No. 4 St. John’s. . . . Damascus continues to knock on the top 10’s door, preserving its perfect record with wins over Walter Johnson (2-2) and Sherwood (3-2) in the last week.

1. Good Counsel (5-0-3) LW: 1

2. Spalding (5-1-1) LW: 4

3. O’Connell (4-2) LW: 2

4. St. John’s (4-1-3) LW: 10

5. Bethesda-Chevy Chase (4-1-1) LW: 7

6. Bishop Ireton (4-1-2) LW: 9

7. Churchill (4-0-1) LW: 3

8. South River (5-2) LW: 6

9. Arundel (4-1) LW: NR

10. River Hill (4-2) LW: NR

On the bubble: Broadneck (4-0), Damascus (6-0), Whitman (3-0-1)