BROOKLYN — Earlier on this six-game trip, Suns coach Earl Watson looked at his team on the court and said with a smile: “At least I’ll know how to deal with my kids when they become teenagers.”

In his second season, Watson, 37, is optimistic by nature, but this latest stretch has tested that to a degree. In Thursday’s loss to the Brooklyn Nets,  Watson sent out the youngest starting five in NBA history, according to Elias.

Listed youngest to oldest

• Marquese Chriss, a 19-year-old power forward who has started most of his first season. Tough beyond his years, but still a pup.

• Derrick Jones, Jr., an athletic wing who is one of the NBA’s top dunkers. He turned 20 last month.

• Devin Booker, a second-year guard considered among the league’s best young scorers, but at 20, still a long way from the legal drinking age.

• Tyler Ulis, an energetic rookie point guard who turned 21 in January.

• Alex Len, a fourth-year, 23-year-old center born on June 16, 1993, the day Charles Barkley and the Suns faced Michael Jordan and the Bulls in Game 4 of the NBA Finals. (The Suns lost, 111-105. Barkley had a triple-double but Jordan went for 55.)

Average age: 21 years, 14 days.

GET MORE ON THE SUNS XTRA APP: iTunes | Android

That broke the previous mark, set by the Clippers in 2010 when shut-down Phoenix point guard Eric Bledsoe was part of a lineup that averaged 21 years, 143 days.

Perspective: Of the eight college teams playing in Thursday’s Sweet Sixteen, the Suns’ starting five was younger than all but one, according to Elias. Purdue. Gonzaga had the oldest group at 22 years, 150 days.

Overall, this is nothing new for the Suns. Entering Thursday, they had set the franchise record for youngest starting lineup five times this season. It’s just gotten worse lately because of management decisions (three veterans have been shut down for the season) and bad luck.

Reserve forward Alan Williams missed Tuesday’s game with a stomach issue. Williams returned Thursday but starting forward T.J. Warren was ruled out with what the team called a left foot contusion. Add in Ronnie Price’s minor leg injury, and that left Watson with nine available players — and the youngest starting five the NBA has ever seen.

GET SOCIAL: Follow azcentral sports on Facebook | Twitter

Perhaps the craziest part of this: The Suns still could get younger. Forward Dragan Bender, the NBA’s youngest player at 19 years, 127 days, has missed the last six weeks after undergoing minor ankle surgery. Watson, however, said the Suns remain hopeful he returns sometime this season.

“I had four teenagers at the age of 37,” said Watson, which was the case at the beginning of the season. “Over night.”

The Suns have lost six in a row. They visit Boston on Friday.

Contact Doug Haller at 602-444-4949 or at [email protected]. Follow him at Twitter.com/DougHaller.