Lampard will be relieved at the crucial victory and the way his side kept going to finally find a way through Stoke's well-drilled defence.
Viktor Johansson was in the mood to frustrate Coventry and kept out a powerful free-kick from Victor Torp before he touched a curling effort from the same player over at full stretch.
Stoke had their moments and Coventry goalkeeper Carl Rushworth denied their captain Ben Wilmot at the back post before Million Manhoef saw a header drift just wide.
The Potters continued to press and Bae Jun-ho had a shot blocked before Manhoef saw another effort deflected wide.
Coventry had scored at least twice in each of their last eight games and Lampard's goal machine continued to try to break down Stoke's resolute defence.
Johansson thwarted them again, getting down well at his near post to save Mason-Clark's 20-yard effort, but Coventry got their reward when Ellis Simms flicked a long throw on for Mason-Clark to finish into the top corner for their 40th Championship goal this season.
Mason-Clark, who suffered an injury in the act of scoring, was stretchered off and Coventry had to survive 16 minutes of stoppage time to claim the win.