Charlton made the perfect start, with Rutherford firing low past keeper Lucy Thomas after a Beth Roe corner had been headed clear.
The hosts had the lion’s share of the possession in the first 10 minutes, though few chances were created by either side, Roe shooting wide with the best.
Coventry began getting themselves into the contest after that, with a succession of corners eventually cleared by Charlton.
The visitors’ best early chance came from a ball over the top that was pulled back for Toussaint, but the winger’s effort was blocked and claimed easily by Cumings.
Another Coventry corner 20 minutes in caused chaos in the penalty area, but Charlton were able to clear their lines, turning it into a counter attack that was foiled by an offside flag.
Another chance falling to Coventry came when a Rutherford backpass fell short and Hardy pounced, advanced on goal but could only see her effort well parried at the near post by Cumings.
Charlton looked like they would end the first half on the front foot. Rutherford spread a ball wide for Wynne and her centre for Hughes saw a flick deflected wide for a corner. The set piece from Roe was headed goalwards by Godfrey, but Thomas made a good save to deny the centre half.
Moments later It was Wynne’s turn to float a deep cross to the back post that was met by Sulola but again the midfielder found Thomas too good.
Filbey and Skeels had long-range efforts easily gathered by Thomas before the away side struck with the last kick of the period when a Green corner floated high and all the way into the far side of the net.
Coventry had the first attempt of the second half but Wilkinson’s effort was blocked.
Charlton then controlled the rest of the opening exchanges, with the Midlander's barely getting out of their own half.
Newborough did well to win the ball on the byline and play Hughes in. The striker’s cross to the back post was guided goalwards by Wynne, but Thomas did well to push it onto the crossbar and foil the follow up. Godfrey’s header from the set piece was cleared off the line.
Charlton were back in front in identical circumstances as the Coventry equaliser after 58 minutes, with Roe’s corner eluding everyone and nestling in the far corner.
Just after the hour mark, Filbey almost extended the Addicks’ lead, firing a 25 yarder towards the top corner but inches over before a dangerous Wynne cross was cleared for a corner.
It was three 20 minutes from time when Cumings played a long ball forward that Skeels did well to win high up the field and lay off to Hughes, who turned her marker skilfully and laid off for Rutherford to lash home from just outside the penalty area.
Cumings was finally forced into a good stop when Johnson shot from range but it was one of few forays forward from the away team.
The final stages were cagier as Charlton looked to conserve their lead, with a Becky Jane shot being blocked and Hughes’ follow up saved by Thomas wrapping up the encounter.
Charlton: Cumings, Newborough, Olding, Filbey, Sulola, Wynne (Jane 67), Hughes, Skeels, Rutherford, Roe, Godfrey.
Subs (not used): Hillyerd, King, Heuchan.
Yellow cards: Anna Filbey ’73 (dissent)