Though there were moments, they were flat throughout and got punished by a Manly side that never rose to any great heights, but never stopped trying.
This game always looked like a banana skin, especially with a short turnaround, and the Warriors made it extremely hard for themselves.
Manly have been decimated by injuries – on an even bigger scale than the Warriors – and were winless coming into this match, conceding an average of 40 points a game in the first month of the season.
But the Warriors couldn't gain the initiative, breathing life into the fragile confidence of the Sea Eagles.
They lacked momentum without Addin Fonua-Blake, who is set to undergo knee surgery next week. The club confirmed on Friday that the marquee prop will be sidelined for at least four months, after sustaining a fractured patella, among other damage against the Roosters last week.
Considering the circumstances and the opposition, the first half was one of the Warriors' worst periods of the season.
They dominated possession and territory but couldn't do much more. Their passing was untidy and indecisive, with runners too often in the wrong place.
Although coach Nathan Brown had warned against complacency, the Warriors were down on intensity and it showed.
If there was a way to bungle an attacking opportunity, they found it. There was a pass thrown straight to a Manly player, a shepherd, cheap knock-ons and some aimless fifth-tackle plays.
It didn't help with so many front-line players missing, but it felt like all the good habits they had harvested in the previous weeks went out the window.
Manly opened the scoring through Jason Saab in the 27th minute, and the only surprise was that they hadn't done so earlier. Jake Trbojevic went close twice and Jazz Tevaga did well to deny Lachlan Croker.
When the Sea Eagles finally crossed, it was a beautiful set move from a scrum, with Saab sprinting from his own half to scoop up Cherry-Evans' clever kick.
That seemed to momentarily shake the Warriors from their slumber, with Ken Maumalo crossing in the corner in his 100th game, after soft hands from Roger Tuivasa-Sheck had put Jack Murchie in a hole.
But they couldn't capitalise on more opportunities before halftime, let down by generally laboured attacking play.
Sean O'Sullivan took the Warriors into the lead with a smart solo try in the 45th minute, stepping inside a prop and outpacing the cover.
That should have been the signal to lift, but they couldn't find another gear. While they did well to force consecutive goal line dropouts, the sight of the Warriors unable to fashion a decent opportunity after four successive sets on the Manly line was hard to watch.
It continued a problem seen for most of the season, with their red zone attack often ineffective against a set defence.
Instead of putting the Sea Eagles away, Manly were still in the game, and made the most of a dubious captain's challenge to level the scores in the 59th minute.
After regaining possession, an unfortunate Kodi Nikorima error gifted Josh Schuster his first NRL try, with the five eighth coughing up a simple grubber.
O'Sullivan shanked a late field goal attempt and when Tohu Harris charged down a Manly shot with 40 seconds on the clock, golden point seemed a certainty. But the Sea Eagles worked another opportunity, and Cherry-Evans nailed the 22nd field goal of his career, with his flat shot just clearing the crossbar.
Sea Eagles 13 (J Saab, J Schuster tries; R Garrick 2 goals, D Cherry-Evans field goal) Warriors 12 (K Maumalo, S O'Sullivan tries; K Nikorima 2 goals) HT: 6-6