ADELAIDE has knocked Port Adelaide off top spot on the ladder with a shock 23-point Showdown win in an entertaining affair.

The Crows' shutdown of the Power in the third term, in which they kept their bitter foes goal-less for the first time in a quarter this season, and some final-term magic from Eddie Betts were the driving factors behind the 14.15 (99) to 10.16 (76) triumph at Adelaide Oval on Sunday.

Betts' two stunning late goals ensured the Crows staved off a customary Port fightback to record their first Showdown victory since 2012.

Crows ruckman Sam Jacobs, who kicked three goals and was judged best afield, gave first use of the ball to midfield brigade Scott Thompson (34 disposals, seven tackles), Patrick Dangerfield (32 disposals) and Rory Sloane (21 touches, nine tackles).

Coach Brenton Sanderson praised Adelaide's consistency through Sunday's four terms and claimed he never doubted its ability to upset the highly fancied Power.

"Being down at quarter-time and half-time, there was still incredible self-belief amongst the group," Sanderson said.

"We've had some challenges but great to get some guys back and see a four-quarter performance."

In an opening term riddled with errors, the Crows opened the scoring within the first minute only to see the Power roll over the top of them by kicking the next four goals.

Late goals to Dangerfield and Jacobs ensured the Crows kept within touching distance at quarter-time.

Majors to Jason Porplyzia and Jacobs early in the second term had the Crows on track to reel in the deficit until Jay Schulz responded.

But Port could not keep the Crows at bay as Josh Jenkins goaled late in the stanza to again cut Port's lead to 10 points at the main break.

With Port forced to sub key defender Jackson Trengove at half-time following an ankle injury, the Crows drew first blood to start the third quarter when Thompson goaled from a neat snap.

A sudden downfall of rain dried up goalscoring opportunities until Adelaide hit the front for the first time after 13 minutes through Betts.

The Power were on the ropes when Taylor Walker toe-poked the ball home to give the Crows a two-goal lead.

The Power had the last five inside 50s of the quarter but could only register four minor scores as the Crows held on to lead by 10 points at the final break.

The Crows, spearheaded by Betts, then pulled clear in the final term as they booted five goals to three.

Port coach Ken Hinkley said the loss was a timely reminder for his players that at the elite level, anything other than a side's best will likely be punished.

"We just know in AFL football that you have to be there week, you have to be there every moment of every week," Hinkley said.

"Every week we get reminders in this game that if you're off a little bit, you're in trouble."