In the green room at the Barclays Center on Thursday, Kevon Looney waited. And waited. And waited.

Finally, he and his party stood and left their table. More than 20 picks had come and gone already in the 2015 NBA Draft, and Looney — once talked about as a potential lottery pick — was still without a home.

But a few minutes later, that changed. His agent had heard word that the Golden State Warriors were about to select the UCLA forward with the No. 30 pick. Looney and his family zipped back.

“It was just nerveracking,” Looney said later. “I got a little stiff and sore; I was sitting there a long time. It was a long wait. You never know what’s going to happen.”

As a freshman, the 6-foot-9 prospect had showed off both his rebounding acumen (9.2 boards per game) and his potential as a 3-point shooter (41.5 percent on 53 attempts). Many mock drafts had him as a top-20 selection, even as his stock slipped over the past few months.

Health concerns likely contributed to the fall. Looney underwent a hip operation last summer, although he didn’t seem to show much rust as he averaged 11.6 points in 30.9 minutes for the Bruins. An NBA executive told DraftExpress that Looney was flagged not only for his hip, but for a degenerative condition in his back that could require surgery in the future.

Looney is the second straight No. 30 overall pick that UCLA has produced, following Kyle Anderson’s selection by the San Antonio Spurs last summer. Five Bruins have become first-round draft picks in the past three years.

“It’s a blessing to be drafted by the champs,” Looney said. “I watched them all season. I watched them in The Finals all year, and to go get drafted by them guys is a blessing. I can’t wait to get out there and play.”