Saints upset Fremantle to mark Lyon's return as coach

St Kilda coach Ross Lyon says his developing AFL side will take a huge amount of belief out of a shock 15-point win over his former side Fremantle.

The injury-hit Saints were at long odds to challenge last year's beaten semi-finalists and trailed by two goals late in the third quarter at Marvel Stadium on Sunday.

But they kicked the final five goals of the contest to give Lyon the perfect start to his second stint in charge with a 10.7 (67) to 7.10 (52) victory.

"It's always nice to get the four points and reward for effort," Lyon said.

"We've had a big summer of hard work and change ... and I couldn't have asked more from the players in attitude.

"(It's pleasing) just to see a group that works really hard and has bought in get rewarded.

"Freo threw a few different things at us and I thought we adjusted.

"(Four-times premiership coach) David Parkin used to talk about it's important to win your first one to get some belief and some confidence, and we know it gets hard from here."

Neither side led by more than two goals in the scrappy contest until St Kilda surged with last-quarter majors to Mason Wood (two), Jade Gresham and makeshift forward Zaine Cordy.

The deflated Dockers had no answer, posting 0.4 to the Saints' 4.1 in the decisive final term despite winning the inside-50 count 21-13.

The visitors managed just two goals from 40 inside-50s in the second half.

There were question marks around St Kilda's scoring ability without key forwards Max King and Tim Membrey, among at least half a dozen players missing from their best side through injury.

But Wood, Gresham and Mitch Owens kicked two majors each to help get their side over the line.

Brad Crouch (30 disposals), Ryan Byrnes (27) and Jack Steele (27) won plenty of the ball as Mattaes Phillipou and Anthony Caminiti both showed glimpses of promise on debut.

Fremantle coach Justin Longmuir admitted his side lacked energy in the first half and didn't match the Saints' effort in the contest.

'It's a wake-up call," Longmuir said.

Fremantle defenders Brennan Cox, Luke Ryan and Hayden Young ran up huge possession tallies as they regularly chipped the ball around in defence.

The Dockers' slow ball movement gave St Kilda plenty of time to get numbers back and set up well defensively, making life difficult for their opponents.

"I don't mind us chipping the ball around but there's got to be some method to it and I thought we just went lateral to occupy the ball," Longmuir said.

"That's not really how we want to play, so we need to get the balance right between making the opposition defend and not having enough dare."

A pair of 50m penalties against Callum Wilkie and Jack Steele for backchat to umpires cost St Kilda two goals as Fremantle hit the front during the second term.

The Dockers led by six points at the final change but St Kilda finished full of running to complete a stunning upset.

Lachie Schultz (two) was Fremantle's only multiple goal-kicker as superstar Nat Fyfe went goalless from just nine disposals in his new role deep in attack.