Coventry boss Mark Robins called on his side to start climbing the League One table after their last-gasp 1-0 win at Oldham.
The Sky Blues snatched their first win since relegation from the Championship thanks to a 90th-minute goal from sub Cody McDonald.
Fellow strugglers Oldham created the better chances at Boundary Park, but their finishing lacked conviction and visiting keeper Joe Murphy made fine saves from Christian Montano and Matt Derbyshire.
Jose Baxter also hit the woodwork with a 25-yard thunderbolt, but the Latics could not force their first home win of the campaign.
Instead Coventry, who struggled up front until the closing stages, struck through McDonald's stooping, close-range header from a Jamie Reckford cross.
And Robins - who recently took over from Andy Thorn - said: "It's amazing what three points can do.
"I'm delighted, it's a relief to get a victory and hopefully this will be the result that gets us moving forward."