A second-half header from captain Jack Parkinson gave Welling a deserved three points at Crabble in Blue Square Bet South on Saturday against Dover.
But the Wings were grateful to new keeper Craig Holloway for a brilliant 89th-minute penalty save in only his second game for the club to ensure their victory.
Holloway dived low to his left to push away substitute James Walker's spot-kick after Walker had been bundled over in the box by Ben Martin.
A tight opening 45 minutes saw few chances at either end, although Jemal Johnson looked Dover's most dangerous player.
Welling took a stranglehold on the game in the second half and Luis Cumbers' lob hit the bar before Parkinson thumped home a Ben Greenhalgh cross after 78 minutes to put them ahead.
In injury time, Wings substitute Joe Healy - playing his first game back after a four-match suspension - was sent-off for the third time this season after receiving two yellow cards in the space of a few seconds for deliberate time-wasting, and he now faces a three-match ban.
The win leaves Welling in third spot, 12 places above Eastleigh in sixth, while Dover, who suffered only their second home defeat of the season, drop down to seventh. Welling travel to Staines in the league on Monday night.
Was a Welling victory a fair result? Leave your comments below.
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