Perth threw East Perth’s finals charge into disarray with a shock five-point win at Lathlain Park on Saturday.

The cellar-dwelling Demons upset 14.14 (98) to 13.15 (93) victory leaves the fifth-place Royals in a precarious situation with one game to go in the home-and-away season.

Luke Webster’s men could have guaranteed their place in the finals series with a win but they now need to beat ladder leaders Subiaco at Leederville Oval or rely on Claremont to record a marginal win against West Perth at Claremont Oval.

Perth were on their game from the first bounce and jumped out to a 20-point lead following two goals from 2017 AFL Draft prospect Cody Ninyette and a lone major from midfielder Corey Byrne.

West Coast Category B Rookie and WAFL league debutant Tarir Bayok sparked a Royals’ first-quarter comeback with the team’s opening goal in the 21^st minute, which was followed by majors by Jake Waterman and co-captain Patrick McGinnity.

East Perth established a 15-point lead at the main break following a four-goals-to-two second term, but Perth rallied in the penultimate quarter to reduce their deficit to just four points with 20 minutes to play.

The Royals looked to have wrapped up the match when they kicked the first three goals of the final stanza, but the Demons dug in and booted a trio of goals to record one of the upsets of the season.

Experienced Eagle Sharrod Wellingham amassed 35 disposals, 12 contested possessions, eight marks and seven inside 50s, Chris Masten and Fraser McInnes got their hands on the ball 21 times, while Jordan Snadden continued his rich vein of form with 26 disposals, 11 contested possessions, 10 half-back rebounds, five tackles and a goal.

Willie Rioli collected the Burley 19 times, reeled in six marks and stuck three effective tackles, Waterman kicked three goals from 14 disposals and Bayok booted two goals in his first game in the Royals’ top team.

Will Schofield pushed forward to slot two goals, Jackson Nelson distributed the ball efficiently with his 15 touches, the same tally as half-back/midfielder Kurt Mutimer, who also won nine contested possessions.

Defenders Francis Watson and Tom Gorter gathered the ball 12 and eight times respectively, while ruckman Jonathan Giles won 55 of his 87 ruck contests.