The Woodbridge and Osbourn girls tennis teams thought the fourth singles position might be pivotal yesterday, but neither could have envisioned the match shaking out as it did in the 6-3 road win that clinched the Cardinal District title for the Vikings.

At that fourth singles spot, Woodbridge sophomore Rachel Heberer played her best match of the season in a 6-1, 6-1 victory over Osbourn senior Liz Hemmer, who aggravated a knee injury that prompted her to withdraw from doubles competition.

With the Vikings leading 4-2 after singles, Osbourn needed a doubles sweep. But with Hemmer hobbled, it never got that chance.

"That was a tough one for us," Osbourn Coach Anne Yeatts said. "When you play hard on every point . . . it's kind of hard to lose that way."

Woodbridge Coach Lewis Forrest said Heberer would have been difficult to handle yesterday even for an opponent with the healthiest of knees.

"I don't know if it was as much their girl being off or our girl being on," Forrest said. "I haven't seen her play like that in the two years I've had her. I don't know if there is any four who could have beaten her the way she was playing. She had the complete game."

With the victory, Woodbridge (11-0) won its 22nd consecutive district match and earned a bye in the first round of the Cardinal tournament, which begins Thursday. Osbourn (9-2), whose two losses were to Woodbridge, will host the seventh seed.

Because of matches today, seedings have not been finalized, though Gar-Field and Osbourn Park are the front-runners to finish in the third and fourth slots, respectively.

Osbourn had lost, 5-4, to Woodbridge in the teams' first meeting this season, and the Eagles thought they had a chance to reverse that score yesterday before Hemmer, who has worn a knee brace this season, got hurt. Hemmer won her No. 4 singles match against Woodbridge in the teams' earlier match.

Yeatts said she did not know whether Hemmer would be able to play in the first round Thursday. The semifinals are Monday.