The Sky Blues won 3-0. Callum Ball gave them a 28th-minute lead and Cyrus Christie's first senior goal killed the game off after 63 minutes before Steven Jennings added a third late on.
The margin of victory could have been more as Franck Moussa and Jamie Reckord both hit the crossbar, and Coventry wasted a host of chances - much to the frustration of Robins.
"We should have scored a lot more goals," said Robins. "You have got to give them a lot of credit, they have come here and tried and they gave us a good game. But we let them give us a good game.
"I thought we were lacklustre and that is symptomatic of us, we wait for things to happen to get us going and it doesn't happen. We have to be more grown-up than that and make it happen for ourselves.
"Cyrus Christie lit the blue-touch paper a little bit in the second half with his runs down the right and that is what you want to see, we need to get bodies in the box and capitalise and score goals. It was a poor start but you have got to credit them and the way they came and set about their jobs because we found it tough to break them down."