Dean Morgan opened the scoring in the seventh minute, heading home Sam Wood’s in-swinging free-kick, however, the visitors hit back five minutes before the break through Freddy Eastwood.
It was left to summer-signing Craig to secure the three points in the 32nd minute when the evaded his marker to power home Max Kretzschmar’s corner.
Matt Bloomfield returned to the squad for the first time in over a year, while Gareth Ainsworth was forced into one change with the suspended Charles Dunne replaced by Kortney Hause.
The visitors started well and Barry Corr’s looping header forced Matt Ingram into the first save of the game in the fifth minute.
However, it was the Blues who took the lead two minutes later. Wanderers won a free-kick wide on the right and Sam Wood’s inviting free-kick was met at the far post by Morgan for his third goal in two minutes.
It was good movement from the striker and the finish was not too dissimilar to his first at Oxford last week.
Southend responded well though and were level five minutes later when top scorer Freddy Eastwood converted Ryan Leonard’s cross from close-range.
Leonard saw a speculative effort deflect over in the 17th minute, before Gareth Ainsworth was forced into his first change a minute later when Josh Scowen limped off to be replaced by Max Kretzschmar.
Ingram did well to prevent an own goal soon after when he parried away at the far post after a Wanderers defender had inadvertently headed towards their own goal. Blues’ keeper then used his legs to save from Leonard after the ball had bounced to him in the area.
The visitors had begun to get the upper hand, but it was Ainsworth’s men who struck again just past the half-hour mark. Kretzschmar did superbly well in the build-up as Morgan won a corner, and the midfielder swung it into the near post, where Craig met it powerfully to give Dan
Bentley in the Southend goal no chance.
Craig was seeing much of the ball and he flashed a shot wide from a narrow angle following Kretzschmar’s clever pass, before just being unable to get on the end of Nick Arnold’s low cross.
Southend were inches away from levelling in first-half injury-time when John White’s header crashed back off the crossbar and the Chairboys then threw their bodies on the line in the subsequent goalmouth scramble before Corr shot wide.
The Shrimpers were fast out of the traps after the restart and Ingram did well to parry away Eastwood’s header from Ben Coker’s cross – Craig cleared the resulting corner off the line.
A quick counter from the visitors saw the ball hooked across to Craig Reid and his first-time volley looked destined for the top corner until a fine block from Leon Johnson saw the ball land on the roof of the net.
Leonard and White both fired high over the bar for the visitors, but again there were a coat of paint away from an equaliser in the 68th minute.
Wycombe failed to clear their lines and Ingram pushed out Straker’s effort, the ball rebounded back to the former Blues loanee and he thumped a shot against the bar.
Bloomfield was introduced to a rousing reception 18 minutes from time and featured on the right-hand side of midfield, with the impressive Kretzschmar continuing to partner Knott in the centre. Ainsworth’s final change saw goalscorer Craig replaced by Matt McClure with 10 minutes left on the clock.
Morgan almost made it a comfortable final few minutes after being put through on goal by Bloomfield, but his left-foot strike hit the bar with Bentley well beaten.
However, the Blues were never really tested, despite six minutes of injury-time, and went on to secure their second victory of the season.
Wanderers: Ingram, McCoy, Hause, Doherty (c), Johnson, Arnold (Bloomfield 72), Scowen (Kretzschmar 18), Knott, Wood, Morgan, Craig (McClure 80).
Subs: Harrison, Spring, Pittman, Kuffour.
Southend: Bentley, White (c), Coker, Prosser, Thompson, Atkinson (Payne 81), Clifford (Hurst 52), Leonard, Straker, Eastwood, Corr (Reid 52).
Subs: Smith, Timlin, Auger, Williams.
Attendance: 3,533 (859 away)