Canterbury controlled the first half, but found themselves trailing after 15 minutes when Sam Kasiano's poor pass 20 metres out from the Manly line was intercepted by Kieran Foran.
Manly halfback Daly Cherry-Evans then spread the play wide, and a classy Lyon flick pass found Williams, who sprinted to the line.
The Bulldogs could have had at least three tries in the opening 20 minutes, with Jamal Idris spilling the ball as he crossed the line and a floated pass to Steve Turner adjudged to be forward with the line at the winger's mercy.
However, the visitors' persistence finally paid off in the 26th minute when Josh Morris pounced onto a Joel Romelo grubber-kick to score, but Turner missed conversion kept the Sea Eagles in front.
Three minutes later, the Dogs felt they should have been awarded a penalty try when Trent Hodkinson, against his former team, broke clear and freed David Stagg.
The back-rower looked almost certain to score, only to be tackled without the ball by Foran, who was subsequently sent to the sin-bin.
Hodkinson's influence on the game continued as the Bulldogs, the last away team to taste victory at Brookvale in round 26 last year, continued to dominate.
A quick break from his own scrum deep in his own half, was halted by Anthony Watmough and Michael Robinson.
But with Hodkinson on the ground with a calf injury from the subsequent tackle, the man who replaced him the Sea Eagles' No.7 shirt Cherry-Evans slotted home a field goal two minutes from the interval to open up a 7-4 lead.
However, with seconds remaining in the first half, Glenn Stewart's floated pass was picked off by Jonathan Wright, and the winger charged 40 metres to score.
Hodkinson's only lasted two more minutes after the interval before limping off the field, and Manly took full advantage with two tries in nine minutes from Stewart and Lyon to open up a comfortable advantage.
But the Bulldogs' response was swift, with Brent Kite losing the ball from the subsequent kick-off following Lyon's try, and Barba latched onto his own grubber-kick to score to cut the hosts' lead to 19-16.
The Bulldogs' continued to press, and Barba looked set to score following a superb flicked pass from Idris.
However, the diminutive fullback was unable to keep control of the ball and the chance went begging.
It proved to be costly for the Bulldogs, with the impressive Cherry-Evans releasing Matai, who took advantage of a hesitant Bulldogs defence and run unchallenged to the line.
And in the final play of the game, Lyon kicked his fifth goal of the game to add some further gloss to the scoreline.
MANLY 27 (J Lyon S Matai G Stewart D Williams tries J Lyon 5 goals D Cherry-Evans field goal) bt CANTERBURY 16 (B Barba J Morris J Wright tries S Turner 2 goals) at Brookvale Oval. Referee: Gerard Sutton, Jason Robinson. Crowd: 12,250.
- AAP
