WASHINGTON — Time is the enemy of the Washington Mystics as Friday’s Game 3 of their WNBA semifinal series against the Atlanta Dream approaches.

Mystics All-Star forward Elena Delle Donne is questionable after leaving Game 2 with what was later diagnosed as a left knee bone bruise. She sat out Thursday’s practice to receive treatment in hopes of getting ready for Friday.

“She’s tough. If she can play, she will,” Mystics coach Mike Thibault told the Washington Post. “We’ll see. It’s been kind of round-the-clock rehab.”

The best-of-five series between second-seeded Atlanta and third-seeded Washington is tied 1-1, with Game 3 to be played at the Charles E. Smith Center on the campus of George Washington University. Game 4 will also take place at the Smith Center on Sunday.

Delle Donne’s left knee bent awkwardly on a drive to the basket with just over three minutes remaining in Tuesday’s game. She was helped off the court by teammates and tests Wednesday revealed no ligament damage.

Delle Donne is averaging 26 points and 13 rebounds in three postseason games this year. She had 27 points, 14 rebounds and six assists in Game 2 as Washington built a double-digit lead before Atlanta rallied.

Washington led 70-68 when Delle Donne went down, but lost 78-75 after failing to make a field goal in the final two minutes.

Alex Bentley came off the bench to score 22 points for the Dream. Jessica Breland finished with 10 points, 14 rebounds, two assists and a franchise-record seven blocks. Bentley has averaged 20.5 points in Atlanta’s two playoff games, with Tiffany Hayes adding 17.0 per game.

The Dream already were missing star Angel McCoughtry, who went down late in the season with a knee injury.

Atlanta outrebounded Washington 44-26 in Game 2 and received a boost off the bench from 6-foot-7 Imani McGee Stafford, who contributed four points and three rebounds in eight minutes after sitting out Game 1.

“I knew Imani was champing at the bit to give us some minutes,” Dream coach Nicki Collen told ESPN.com. “She gave us good minutes. We just wanted to give (the Mystics) a different look in short spurts.”

Washington went 1-3 without Delle Donne in the regular season. Tianna Hawkins stepped in and averaged 12.8 points and 6.8 rebounds during that stretch.

“We didn’t really talk about her today, actually,” Mystics veteran guard Monique Currie told the Post regarding Delle Donne. “We just went through practice as we normally would. Obviously, we’re hoping that she’ll be fine for tomorrow, but we know that we have to be prepared for her not to be.”

Kristi Tolliver is averaging 11.7 points per game in the playoffs for Washington, second most behind Delle Donne.

Breland, the WNBA’s third-leading shot-blocker (1.91 bpg) this season, was named to the league’s all-defensive first team. Hayes and Ariel Atkins of the Mystics were named to the second team.