Manu Vatuvei had a poor return to first grade and there will be questions over the decision to keep Tui Lolohea on the bench until the extra-time period.
Credit must go to Manly, who produced one of their best performances of the season. They completed their first 23 sets before finally coughing up a mistake in the 54th minute.
The result continued some some significant hoodoos. The Warriors now haven't won in Perth in eight attempts, dating back to their first game in Western Australia in 1996. And the Sea Eagles have been like Kryptonite for the Warriors, with 11 defeats from their last 12 encounters. Errors dogged the Warriors. The conditions made it tough, but there has to be some adjustment. The visitors didn't, with ambitious no-look passes from dummy half and not enough care when playing the ball. And they still lacked the finesse with their fifth-tackle options, with Issac Luke guilty of overdoing the kicks from dummy half.
It was a frustrating night, with periods of wholehearted endeavour and quality followed by a lapse. After their second try, they knocked on from the kickoff and later dropped the ball on the first tackle after gaining a penalty in Manly territory. It continued in the second half, when they worked hard to force a line dropout before throwing the ball over the sideline.
Manly made the perfect start, with fullback Tom Trbojevic slipping through Blake Ayshford's tackle in the third minute before Jorge Taufua crossed nine minutes later. Nothing went right for the Warriors in the opening stanza, with a string of mistakes, cheap penalties and almost no possession - just one completed set - in the first 15 minutes.
Given that start, they showed impressive character to turn things around, when in the conditions things could have gone south very fast. They worked their way back into the match, with Bunty Afoa crossing twice in the space of six minutes. The tries were almost carbon copies, with Afoa running off a perfectly-timed Johnson pass on both occasions. Jamie Lyon nudged the Sea Eagles in front, after another unfortunate penalty, before Luke levelled with five minutes to play.
The Warriors dominated possession for most of the second half, and forced several line dropouts, without creating too many clear-cut chances. Solomone Kata came closest, but dropped a Thomas Leuluai grubber over the tryline. But they were lucky to get to golden point, after Manly blew two glorious opportunities in the dying minutes of the match before Cherry-Evans' decisive strike.
Sea Eagles 15 (T Trbojevic, J Taufua tries J Lyon 3 goals, D Cherry Evans drop goal)
Warriors 14 (B Afoa 2 tries, I Luke 3 goals).
Halftime: 14-12.