Matt Tropsha sat in the Club Room at the University of Minnesota's Baseline Tennis Center on Tuesday, doing his best to adopt a casual attitude after winning the biggest match of his life.

It wasn't working.

"I'm just trying to be cool," the Wayzata junior said, trying to suppress a wide grin. "We've got two more matches to go."

Playing No. 2 singles for a Wayzata team that has been undermanned all season, Tropsha battled back from a first-set loss to defeat Eden Prairie's David Zhou 2-6, 6-3, 6-3. That gave the Trojans a 4-3 victory over their Lake Conference rivals in the quarterfinals of the Class 2A boys' tennis tournament.

Wayzata has played most of the season without its top singles player, Dustin Britton, who still is recovering from a shoulder injury.

Injuries have ripple effects in team tennis, forcing players out of their usual slots and, in theory at least, weakening the team.

Wayzata coach Jeff Prondzinski wasn't having any of it. No sympathy. No excuses.

"We're a scrappy team," said the equally scrappy Prondzinski. "We weren't feeling sorry for ourselves. We can win with the team we have."

Eden Prairie, which has battled injuries of its own, looked formidable, much like the singles-heavy team that won the Class 2A title in 2010.

So Prondzinski put Wayzata's strength in doubles and hoped a singles point could be found somewhere.

Enter Tropsha, a determined lefty who makes up in on-court savvy what he lacks in power.

After a shaky first set, he settled in, found his game and outwaited Zhou.

"I toned it down in the second set and tried to control the points," Tropsha said. "I played smarter."

In the other Class 2A quarterfinals, Eagan, flip-flopping Wayzata's strategy, won three singles points and stole a victory at No. 2 doubles to beat defending champion Rochester Mayo 4-3; No. 1-ranked Elk River ran its perfect record to 29-0 with a 5-2 victory over first-time entrant Maple Grove; and Mahtomedi swept all three doubles matches to defeat St. Cloud Tech 5-2.

Eagan's victory might have surprised some, who looked at the return of Thomas Nath and Ingrid Neel from injuries as reasons to elevate Mayo to a favorites role.

Eagan coach Scott Nichols knew differently. With the exception of the highly ranked Nath, Nichols felt his Wildcats were stronger in singles and would be able to win at least one doubles match.

"I told the team that, if they played like they did in the section [finals], they couldn't lose," Nichols said.

The match went as Nichols expected, boiling down to No. 2 doubles between Eagan's Andrew Finnegan and Dylan Mannetter and Mayo's Neel and Sawyer Bock, who had little experience together.

In the three-set nail-biter, it was Finnegan and Mannetter who came through, hitting with authority and repeatedly beating the Mayo duo at the net for a 6-4, 3-6, 6-4 victory.

"You have to take your hat off to Eagan," Mayo coach Jeff Demaray said. "They went out and beat us in a doubles match we didn't think they could win."

While Mayo faltered under the pressure, Finnegan said that playing in the spotlight was just what they needed.

"We enjoy playing with pressure," he said. "We got that extra boost from everyone cheering for us."

Class 1A

There were no surprises in the Class 1A quarterfinals at the sweltering Reed-Sweatt Tennis Center in Minneapolis.

Breck, the No. 1-ranked team in Class 1A, defeated Duluth Marshall 7-0 and No. 2-ranked Blake shut out Thief River Falls by the same score, setting up a semifinal match that will play like a championship final.

On the other side of the bracket, Mound-Westonka downed Fergus Falls 4-3 on the strength of three-set singles victories by Arend Turner and Sander Lee. The White Hawks will face Rochester Lourdes, which routed Luverne 7-0, losing a total of only seven games.