Don't be fooled by the scoreline. The Broncos deserved to lose by 20 and Bennett knew it, later delivering a stinging assessment when asked if his side had the defensive steel to break their 11-year title drought.
"We'd be lucky to beat the teams 15th and 16th with that defensive effort," a deflated Bennett said.
"Everybody was getting excited in the coaching box (after Ferguson's blunder) but I wasn't, I didn't think we could win.
"The Broncos are brave, but we didn't play well. We are so far off being what we could be.
"We turned some things around (in the second half), but we weren't consistent enough and the errors just killed us."
Trailing 14-6 at half-time, the Broncos did well to hang tough and almost snatched a remarkable victory before Mitchell sliced through to save Ferguson from a post-match mauling.
On match eve, Bennett said he wasn't concerned by Brisbane's worrying habit of slow starts. He should be.
During the regular season, Brisbane leaked 25 tries in the opening 20 minutes of games. The Broncos should have rectified their first-quarter intensity for the finals.
Instead, they looked liked they'd been injected with valium as the revved-up Roosters ripped them apart in midfield with a lethal fusion of pace and power.
Brisbane's first half wasn't mediocre. It was worse. It was stupefyingly sloppy.
Everything about the Broncos' start was chaotic. Coach Bennett sensationally dropped fullback Kodi Nikorima to the bench and called David Mead into the backfield. Benji Marshall remained at halfback. It could be viewed as a kick in the guts for Nikorima, who was Brisbane's starting No.7 just a week ago.
"I thought we would take a bit of pressure off Kodi, that didn't affect us," Bennett said.
Bennett needs more from his halves. Marshall struggled to dominate at halfback, while pivot Anthony Milford was brutally exposed in defence last night, missing seven tackles and conceding two tries.
"At times, we weren't the Broncos," prop Adam Blair said. "We didn't play how we wanted to play ... too many errors."
SYDNEY ROOSTERS 24 (B Cordner A Guerra L Keary L Mitchell tries M Gordon 4 goals) bt BRISBANE 22 (C Oates 2 B Hunt J Roberts tries J Kahu 3 goals) at Allianz Stadium. Referee: Matt Cecchin, Alan Shortall. Crowd: 21,212