But this latest defeat for Cheltenham Town leaves them at the foot of the League One table.
Stockport made a blistering start to the game and could have scored twice in the opening three minutes.
Firstly Leon McSweeney saw a shot superbly saved by Town keeper Scott Brown and then loan striker Chris O'Grady smashed a close-range shot against the crossbar.
A super move then saw Tommy Rowe cross in low for Johnson, but he volleyed just wide.
Midway through the first half Cheltenham fluffed a great chance to open the scoring.
Lloyd Owusu flicked a tempting ball into Damian Spencer's path, but he blasted a shot straight at Stockport keeper Owain Fon Williams.
After half-an-hour McSweeney crossed in from the right, and this time O'Grady slid in but couldn't direct his shot towards goal.
Stockport finally got the goal they had been threatening a minute later. Gary Dicker played in youngster Johnson, and he lashed home a brilliant shot into the top corner from just outside the Cheltenham box.
At the other end Spencer fired another shot straight at Fon Williams, but the hosts quickly hit back again when skipper Johnny Mullins came up from the back to hit a half-volley narrowly wide.
Stockport front-man O'Grady was again denied by the woodwork seven minutes after the restart.
Rowe saw an initial shot saved by Brown, but the rebound was crashed against the post by the unfortunate O'Grady.
Minutes later the impressive Johnson - a recent capture from non-league Nostell Miners Welfare - saw a near-post shot expertly beaten away by Brown.
As the final quarter-hour approached Cheltenham upped their tempo, with both Ian Westlake and Alex Russell going close with half-chances.