How do White House VIPs relax on a balmy summer night? Watching tennis under the stars.

Mark Ein, Valerie Jarrett, Tina Tchen, Penny Pritzker and Billie Jean King at Monday’s Kastles match. See a larger crowd shot below. (Rich Kessler)

Yes, that was Michelle Obama and Sharon Malone, wife of Attorney General Eric Holder, at the Washington Kastles season opener Monday night. Across the court, presidential adviser Valerie Jarrett, Commerce Secretary Penny Pritzker (who barely dodged a sizzling ace that rocketed past her front row seat), FLOTUS’s Chief of Staff Tina Tchen, and tennis legend Billie Jean King cheered on D.C.’s World Team Tennis champs.

The power fans come out in droves for Washington’s most successful (if least heralded) sports franchise. Why? They may not have time to play anymore “but I love watching,” Jarrett told us. She grew up playing tennis every weekend in Chicago, and makes a point of coming to at least one Kastles match every year. It’s good for the city, she said, and even more fun now that the team has two undefeated seasons. “Everyone likes to win.”

First lady Michelle Obama at Monday's Kastle's opener. (Katherine Frey/The Washington Post) First lady Michelle Obama at Monday’s Kastle’s opener. (Katherine Frey/The Washington Post)

And so they came: The first lady, who kept a lower profile by sitting on the far end of the court. Mayor Vincent Gray, White House chef Sam Kass, Sen. Kirsten Gillibrand, Nationals co-owner Debra Lerner Cohen, Wolf Blitzer, former Redskin John Riggins, former Sen. John Breaux — many of them fans and players of some skill. Obama economic adviser Gene Sperling, unofficially acknowledged as the West Wing’s best tennis player, rushed over from the office but wouldn’t confirm (or deny) the bragging rights: “It’s the course of prudence,” he said.

Sitting in the middle of it all: a beaming Mark Ein, amateur tennis player and enthusiastic owner of a team that includes Venus Williams (injured, so she sat on the bench last night) and now Martina Hingis. Ein and his team scored an Oval Office visit with President Obama earlier in the day Monday — a reward for winning the WTT 2012 title. This season started on a high note: The Kastles defeated the New York Sportimes, extending their winning streak to 33 and tying the Los Angeles Lakers for the pro sports record.   

Kastles owner Mark Ein shows off his championship rings. (Roxanne Roberts / The Washington Post)

Which brings us to Ein’s impressive bling: Three ginormous championship rings.

“The team has done such unbelievable things we wanted to commemorate them the right way,” he said. “This is what we came up with.”

The 2009 ring has a big ruby: “Obviously, the first one is so special.” The 2011 ring marks the first perfect WTT season in 37 years (16 rubies on a diamond field) and the diamond-studded 2012 ring celebrates the second consecutive undefeated season. This was the first time Ein wore all three. “I don’t usually wear these out.” And no — he has no plans to ever show the rings to Vladimir Putin. “I like them too much.”

Related: Washington Kastles run World Team Tennis win streak to 33, beating New York Sportimes

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(Rich Kessler) (Rich Kessler)