Ben Swallow hit two goals and was sent off as the Hawks had to dig in to beat East Thurrock United 2-1 in their third qualifying round FA Trophy tie at Westleigh Park.
Swallow put the home side firmly in the driving seat with two outstanding first-half strikes.
But he was then sent off in the second half for a second bookable offence.
It left the Hawks to negotiate a difficult final 30 minutes as they had to scrap hard before clinching their place in the next round.
Hawks boss Lee Bradbury felt his side did well to hang on to the victory.
He said: ‘We made hard work of it and the sending off was a silly one.
‘The penalty we conceded was the softest I have seen all season and it made a game of it in the final stages when we went down to 10 men.
‘Despite being a man down, we remained organised and hard to play against.
‘We dug in well and worked really hard.
‘But it shouldn’t have come to that.
‘After going two goals up we had chances to kill them off before half-time but didn’t take them.
‘We had enough of the ball to be out of sight.’
The Hawks started well and Swallow deservedly gave them an eighth-minute lead with a stunning free-kick.
After a foul on Perry Ryan, the Welsh winger curled a magnificent strike into the top corner.
To their credit, the Ryman League premier division visitors didn’t allow going behind to ruffle them and Hawks keeper Ryan Young was forced to make a series of vital saves.
On 17 minutes, though, Swallow hit another excellent goal to make it 2-0.
Receiving the ball to the right of the area, the winger stepped inside his defender and rifled an unstoppable shot low into the far corner.
It was almost game over when Scott Donnelly crashed in another curling free-kick which crashed back off the top of the post.
The second half, however, didn’t go to plan as far as the home side were concerned.
On 65 minutes Dan Strugnell was adjudged to have bundled Lewis Harris over in the area, though there appeared to be minimal contact if any at all.
Sam Higgins sent Young the wrong way with his spot-kick and all of a sudden the Hawks were no longer coasting.
Then Swallow, who had been booked in the first half, collected a second yellow card for blatantly pulling back an opponent as the visitors looked to break quickly.
It was a foolish spur-of-the-moment foul, simply because the Hawks player was unhappy he hadn’t gained a free-kick seconds earlier.
The result was an uncomfortable finish for the hosts but they held out, much to the relief of Swallow.
‘Both yellow cards were avoidable,’ said Bradbury.
‘The most important thing, though, is we are in the draw for the next round and I think it is well deserved.’
The draw for the first round proper takes place today.
HAWKS: Young, Strugnell, Blanchett, Ryan, Dutton, Harris, Swallow, Donnelly, Mullings (Connell, 90mins), Bubb (Ciardini, 70mins), Huggins (Przespolewski, 85mins). Subs not used: Woodford, Wedlake.