Mylan World TeamTennis celebrates its 40th birthday this year. For more on WTT, including this season's schedule, click here.

In the last five years, the Washington Kastles have been the Goliaths of Mylan World TeamTennis. The five-time champions (four consecutive) have rarely lost matches since coming together in 2010, and it has truly taken a special effort to unseat a team that, quite literally, refuses to lose.

Playing their first home match of Mylan WTT’s 40th season, the Kastles were fresh from a day of rest and appeared in pole position to begin one of their signature unbeaten runs. Across the net were the Austin Aces, a team playing its sophomore season of Mylan WTT, and one comprised completely of rookies to the professional team tennis league. Alla Kudryavtseva had been a substitute for the Kastles in 2013, but was a veritable David -- to extend the metaphor -- when it came to the demands of playing a full season on the road.

“We’re all rookies, but we’re really catching up to this team spirit and really starting to embrace it,” Kudryavtseva told on Tuesday.

The Aces came to Kastles Stadium at the Smith Center having earned a hard-fought win over the Boston Lobsters in Extended Play on Monday. Kudryavtseva and partner Nicole Gibbs were crucial Austin’s first “ace,” sweeping the women’s doubles before Gibbs emerged after halftime to upset top Draft Pick, Irina Falconi. Against the Kastles, the Austin women were similarly second up after teammate Teymuraz Gabashvili lost a tight set of men’s singles to Denis Kudla.

Facing giants in former No. 1 Venus Williams and Mylan WTT veteran Anastasia Rodionova, Kudryavtseva and Gibbs unwrapped an aggressive game plan to play flawless tennis -- shocking the Kastles and silencing the crowd.

“It was an awesome effort by the whole team today,” Gibbs said. “I thought we played really well in the women’s doubles and I was excited to get off to a good start.”

With Gabashvili and Jarmere Jenkins stepping up in men’s doubles, the five-time All-American had an opportunity to earn an insurmountable lead against Williams in women’s singles. Though she lost the set, Gibbs believed Mylan WTT’s innovative format allowed her to retain her intensity -- even when the five-time Wimbledon champion was at her unplayable best.

“I didn’t play quite as well as I was hoping to in the singles but I was able to put a few points on the board.”

Gibbs passed the baton to Kudryavtseva, who paired with Gabashvili for a one-set shootout in mixed doubles. Up against crowd favorites in Williams and Leander Paes, Kudryavtseva relied on support from her fellow Aces when times were tough.

“Today I felt so much support from my teammates. I mean, everyone else was against us, but my teammates were there for me and I was there for them.

One for all, and all for one!”

The Russians surged to a 3-1 lead, but as the Kastles threatened to keep it close, Kudryavtseva made pressure a privilege as she pulled back on her proverbial slingshot -- belting a final forehand to clinch the match.

“I’ve played some mixed doubles in my life,” Kudryavtseva wryly reminds Mylan WTT fans. “I was like, ‘you know, I’ve got to make something special, otherwise the guys, they don’t let you get away with just a regular shot.’

“I just went for it; we still had some cushion, a few games on our belt. But I’m really glad it went in!”

Watching from the bench, Gibbs felt the gravity of the moment as her team inflicted just the third home loss on the Kastles in four years.

“I was really proud of our mixed doubles at the end, coming through a lot of pressure there against the defending champions in their house.”

Though tennis is an individual sport, Mylan WTT competitors play for much more in each and every match; the Aces certainly took that sentiment to heart when dedicating their incredible win to Austin owner, Lorne Abony.

“I just want to thank Lorne for having us on the team, for bringing us together,” Kudryavtseva said. “We know he’s going through some tough times right now, and we just want to dedicate this win to him, and hope it will bring him strength and luck.”

The Aces return home on Thursday night to make their season debut at Gregory Gymnasium at The University of Texas. With their two stellar wins making them the only undefeated team in the league, Gibbs is looking forward to playing in front of the Austin crowd and predicts even more Aces on the menu as the team soldiers on.

“I think we’re really looking forward to it; I think playing at home will make our lives a little easier and hopefully we can carry some of the confidence and momentum that we’ve taken from these first two road wins forward into our home season.”

Undaunted and undefeated, the Austin Aces have been calling the shots in 2015. With a win over the Kastles, it’s clear that they have good aim.