Wheelchair rugby is played indoors on a basketball court with four players on a side.

The International Wheelchair Rugby Federation calls its sport an “invasion and evasion sport for quadriplegic athletes.”

It is a co-ed sport, but the vast majority of the players at the international level are men.

Warren Area High School graduate Liz Dunn and her teammate Sarah Adam were the first two women ever to play for the United States team at the World Championships when they accomplished that feat this month.

“The objective is to score the most points (tries), and that is done by carrying the ball across the opponents try (or goal) line which is at the end of what we call the key,” Dunn said. “The ball used is very similar to a volleyball.”

Most plays start with an inbound pass, much like in basketball.

To advance the ball, players may carry it or pass. They can’t simply hold onto the ball. “You have to either dribble or pass the ball every 10 seconds,” Dunn said.

Forward passes are allowed, unlike in rugby. Another difference is that only a portion of the end line is the scoring area in wheelchair rugby.

After an inbound play, a team has 12 seconds to cross half-court.

There is a shot clock. “You have 40 seconds total to score,” Dunn said.

The four players work together to advance the ball and score a try.

Only those with disabilities that affect both their arms and their legs are eligible, Dunn said.

“Each player is assigned a classification based on their functional ability,” she said. “The higher the classification number, the more function a player has.”

Players are assigned points from 0.5 to 3.5.

“I am classified as a 0.5,” Dunn said.

Teams may not load up on 3.5 players — the maximum total for the four players on the court is 8.

But, if one or more of those players is a woman, the total goes up.

“For each female on the court you can have an additional 0.5 points,” Dunn said.

When Dunn and teammate Sarah Adam were on the court at the same time for the U.S. in the recent World Championships, their team could have had 9 points in the game.

It is a contact sport.

“Chair-to-chair contact is allowed, however there are a few ways to hit a player that is dangerous and can result in a foul,” Dunn said. “Also, any body-to-body contact is not allowed.”

Fouls can result in a trip to the penalty area for the committing player.

“Chairs are custom built for each player, and are either defensive or offensive,” Dunn said. “Defensive chairs have what we call a picker on the front which is used to help stop other players. Offensive chairs are smooth across the front. I use a defensive chair and it weighs about 35 pounds. They are designed to withstand the contact, although damage to them can occur.”

There are many big, muscular players in wheelchair rugby.

Dunn is not one of them. She gives away height and strength to most.

But, as one commentator said in one of the World Championship matches, “Don’t be fooled. She’s tough.”