A late try could not save Canterbury from their third defeat in four games after a disappointng second half performance.
In a match fragmented by frequent injury stoppages they were subdued and lacking cohesion as they failed to build on their half time lead.
After an ominously slow start which saw league newcomers Rochford take the lead with a try and conversion by fly half Sam Cappaert the city side forced their way back into the game.
The second quarter brought them two tries and by the interval they were looking slight favourites.
The first resulted from intense forward pressure and when Rochford stopped a drivng maul illegaly it cost them a penalty try.
Their next seven points owed everything to pace and vision as Aiden Moss found a gap and Tom Best sent scrum half Tom Williams racing to the posts for Frank Reynolds to convert.
A third try beckoned when Moss opened up Rochford’s mean defence with a chip and chase but a cruel bounce denied him what seemed a nailed on score.
At that point Canterbury were confident and looking in control. Why they could not carry that momentum into the last forty minutes only they will know.
Rochford looked the hungrier outfit, dominated territory for long periods but at least Canterbury showed plenty of defensive grit. It was a surprise when the home side cracked them from a first phase move which ended in an unvconverted try for Jordan Spivey.
An uninspiring and error prone Canterbury then surrendered the lead to a Cappaert penalty goal and Rochford extended it to six points with an opportunist try from George Griffiths.
There seemed little danger when Mark Billings kick reached half way but the ball broke for the home side and the wingman found himself with a clear run to the corner.
When Canterbury did find a couple of attacking positions they were lost through lineout wobbles but they roused themselves in a desperate late surge.
A driving maul try left Reynolds with a hugely difficult kick to win the match. It missed by a whisker but Canterbury will know it was their own shortcoming which really hurt their chances.
Canterbury: W.Waddington, S.Sterling, A.Moss, T.Best, F.Morgan, F.Reynolds, T.Williams, B.Young, T.King, D.Herriott, R.Cadman, J.De Vries, S.Rogers, A.Evans, T.Oliver.
Replacements: J.Otto, A.,Cooper, T Rayleigh-Strutt, B.Cooper, J.Weaver.
Picture supplied by Canterbury Rugby Club.