Genevieve Okoro is great at basketball.

She's also pretty good at math.

"If there are two people on me, that means that one of our girls is open," Okoro said. "If there are three people on me, that means two of our girls are open. We'll take that."

Some games, those numbers will add up a little better for the Eastern girls' basketball team than they did in last night's season opener against Cherokee.

It still was a good night for Eastern. The Vikings, the No. 1 team in The Inquirer Top 10, scored a 45-39 victory over the No. 2 Chiefs in a physical, foul-filled Olympic American clash.

"It was a knock-down, drag-out, heavyweight fight," Cherokee coach Shannon Bretz said.

On paper, this was a great matchup of the No. 1 and No. 2 teams in the rankings, plus a chance for three future Division 1 players to take the floor at the same time.

Okoro has signed with the University of Richmond. Cherokee's Monica Roeder has signed with Manhattan, and the Chiefs' Tiffany Turner has signed with Cincinnati.

"Those girls are going to be playing college basketball at the highest level," Okoro said. "You know they are good. They have an amazing team."

Unfortunately, none of the girls was able to fully display her talent. It was tough for both teams to generate any offensive rhythm, thanks to a combination of first-game jitters, scrappy defense and the near-constant interruption of the referees' whistle.

Don't blame the officials. This was a tough game between familiar foes, with a ton of banging under the basket.

Okoro found a way to score 28 points, while also grabbing 12 rebounds and blocking six shots. She took over in the fourth quarter as Eastern pulled away from a two-point lead to secure the first victory of the long season.

"What can you say about her?" Eastern coach Joe Murphy said. "I feel very lucky to be coaching her. The thing about her is, the way she plays is the way she practices. She brings everybody up to another level."

Eastern will need consistent play from its other athletes if the Vikings are to keep a grip on that No. 1 ranking, win the Olympic American title, and make a deep drive in the Group 4 tournament.

The Vikings struggled to find points from other contributors against Cherokee, although part of that was because of the Chiefs' sturdy defense. Senior forward Nia Blevins scored five, as did reserve junior guard Marlene Pratt.

"It can't just be me," the 6-foot-1 Okoro said. "I thought our other girls played great tonight."

All the Vikings played defense and fought for rebounds and dove for loose balls. All the Chiefs did, too.

Okoro was the difference because of her ability to get the Chiefs in foul trouble. She shot 14 for 16 from the foul line, and she had much more room to operate in the fourth quarter because the Chiefs' best defenders were either leery of a fifth foul or already sitting on the bench after committing it.

"You could see how much easier her last few layups were," Bretz said. "She's got so many weapons. She's a little unorthodox, and that can get you in a lot of foul trouble."

Okoro said she got accustomed to double- and triple- teams late last season, after Eastern's star senior guard, Barrie Cohen, was lost for the year with a knee injury.

"At first it was extremely, extremely frustrating," Okoro said. "But I came to expect it. I know it's going to happen all the time this year.

"To me, teams are taking a risk. If they want to double- and triple-team me, we'll exploit that."

To Okoro, it's a numbers game, and it adds up in her team's favor.

Of course, it also helps when she puts up these kinds of numbers: 28, 12 and 6.

Cherokee 7 14 9 9 - 39

Eastern 11 16 5 13 - 45

C: Amanda Franks 3, Tiara Mosely 5, Monica Roeder 7, Courtney Escudero 13, Tiffany Turner 11.

E: Genevieve Okoro 28, Kerri Aiken 1, Nia Blevins 5, Darian Graziano 4, Michelle Dixon 2, Marlense Pratt 5.

Contact staff writer Phil Anastasia at 856-779-3223 or panastasia@phillynews.com.