STANFORD, Calif. -- As soon as Francis Owusu's mind-boggling, behind-the-opponent’s-back-after-a-trick-play catch happened in Stanford's 56-35 win over UCLA, Christian McCaffrey began shaking.

"I just couldn't believe what I saw," the running back -- who started the play as the Wildcat (formation) quarterback -- said. "I saw him pulling the ball over the guy's back, but I just couldn't believe it. I had to sprint off the field to sit down. I didn't know how to react. I just had to process it."

David Shaw called the play to counter UCLA's aggressive safeties, who he noticed were cheating toward the box in the midst of McCaffrey's school record-breaking 243-yard rushing effort. The design was complex: McCaffrey handed off to speedster Bryce Love on a supposed sweep, but Love pitched back to quarterback Kevin Hogan, who had initially lined up out wide. Hogan then lofted an intentionally underthrown bomb to Owusu, who somehow caught the pass in the midst of heavy pass interference -- by reaching around Bruin defender Jaleel Wadood and pressing the ball against his opponent's back.

Owusu essentially caught both Wadood and the football.

"I saw the ball in the air just for a little bit," Owusu said. "I wrapped my arms around him, and I felt it. And then I squeezed my arms around [the ball] as hard as I could."

At the time of the catch, Shaw -- assuming an incompletion and pass interference -- was already looking down at his play sheet to make the next call. Television cameras then caught the coach's priceless look of incredulity -- a fitting finish to a week that's featured much talk about Shaw's stoic demeanor on the sideline.

"I still can't describe that catch," he said. "I still don't know what happened. I was told my facial expression was all over TV. I still feel the same way now."

SAME @CoachDavidShaw #Pac12FB #Pac12AfterDark pic.twitter.com/GZ8JyXALVF

— Pac-12 Networks (@Pac12Networks) October 16, 2015

The rest of Stanford's sideline agreed. Linebacker Blake Martinez said that players immediately compared it to Kodi Whitfield's circus touchdown reception two years ago -- which also came against UCLA.

"We all thought the play was over with a flag," Martinez said. "That was sick."

Hogan, who claimed to have a perfect view of the catch, said that this was Stanford's first usage of this particular trick play since Andrew Luck found Ty Montgomery with it to reverse momentum in the Cardinal's 56-48 triple-overtime victory over USC in 2011. Stanford had successfully practiced the play earlier this week, but not with Thursday's theatrics.

"It speaks for itself," Hogan said. "It was the greatest play I've ever been a part of."