Some fans claim it cost Adelaide the match, but umpires are defending the decision not to penalise Hawthorn's Isaac Smith for holding the ball on Friday night.

It was one of the best games of the season so far, highly skilled, high-scoring and close.

Hawthorn were three points up and players from both sides flooded Adelaide's forward line, where the ball landed with just seconds to spare.

Smith grabbed the ball out of the air and Rory Sloane wrapped his arm around him to tackle, moments later the Hawks player dropped the ball and the siren sounded.

Speaking to the Whistleblowers program on the AFL's website, umpires head coach Hayden Kennedy said the man on the spot, umpire Shaun Ryan, had made the right call.

"We don't think he [Smith] had prior opportunity before he was tackled," he said.

"There's certainly no prior [opportunity] or illegal disposal, because [the ball] is stripped from him."

The laws of the game say a player will be deemed to be holding the ball if  — among other reasons — he is balanced and steady, so had reasonable time to dispose of the ball, or had an opportunity to dispose of the ball and chose not to do so.

It is also considered to be holding the ball if a player could get rid of the ball, but instead choses to try to fend off players trying to tackle him and gets caught.

Holding the ball can also be paid if a player drops the ball without making a real attempt to handpass or kick it.