New signing Josh Magennis headed the winner in the dying seconds at Wycombe to send Stevenage through to round two of the Carabao Cup.
It was a fitting start to the Boro's 50th anniversary season as substitute Magennis, a summer capture from Exeter, rose to score from Phoenix Patterson's left-wing corner in the fifth minute of second-half stoppage time.
The visitors had shaken off early pressure to take the lead against the run of play in the 27th minute.
Midfielder Dan Kemp took advantage of hesitancy in the Wycombe defence as he raced through to fire home a low shot.
That stung the home side into action and Ewan Henderson equalised in the 38th minute. Winger Silko Thomas crossed from the left and the Scot slipped through the visiting defence to score right-footed from just outside the six-yard box.
Stevenage scared their League One rivals again on the stroke of half-time when Kemp rattled the bar with a shot from the edge of the box.
Wycombe took control after the interval, but struggled to break through.
New boy Emre Tezgel, on for Cauley Woodrow, was thwarted by Boro skipper Carl Piergianni as he attempted to force home Thomas' cross from the left in the 77th minute before Magennis settled the issue.
Match report supplied by PA Media.
