Will Bird’s second-half double proved enough for Holbeach United.
The Tigers made it 13 wins out of 15 games and extended their unbeaten home record this season.
A seventh success from eight league matches at Carter’s Park lifted them into sixth place.
Boss Seb Hayes said: “The last time Bird scored was away to Harborough Town so he was low on confidence.
“He mis-hit two shots and they both went in this time!
“Previously he had chances and the keeper made good saves.
I felt we might have got caught out because of all the injuries but a change of formation benefitted us. We won because we did all the ugly bits out there.Seb Hayes
“I thought we were awful in the first half and better after that.
“We dropped too deep and invited pressure.
“We gave away silly free-kicks but in the second half we got higher up the pitch.
“We are a better side when we are pressing the ball.
“At this stage of the season, it’s not about playing nice football.
“We needed to win because Deeping Rangers and Wisbech Town got three points in midweek as well.
“I felt we might have got caught out because of all the injuries but a change of formation benefitted us. We won because we did all the ugly bits out there.”
Adam Jackson returned to Carter’s Park on dual registration with Spalding United as he regains full fitness following a shoulder injury.
His appearance was agreed by Tulips boss Chris Rawlinson as a favour to Hayes who is dealing with a lengthy injury list.
Holbeach also brought in Lincoln United striker Ryan Oliver on a temporary deal to face Eynesbury Rovers on Wednesday night.
Hayes added: “Spalding have done us a massive favour.
“Hopefully we can help each other out and build a relationship.
“Oliver was playing for Lincoln before he went on holiday but the manager was happy for him to come here and get 90 minutes.
“He grew into the game eventually.
“There was no cohesion in the first half but then we played to his strengths.
“He had a hand in the second goal as well.”
Before the break, the Tigers had to cope with a series of goalmouth scrambles.
Jordan Brown was denied from close range and Rick Drury pushed out Hayden Bream’s 20-yard free-kick.
At the other end, George Zuerner poked off target but Holbeach couldn’t create another clear-cut chance until Bird curled over the bar 12 minutes into the second half.
Bird switched to the right flank but he was also required on defensive duty, clearing off the line from Brown.
Oliver nodded wide when Lewis Leckie’s shot was deflected into his path while Eynesbury’s Danny Draper should have done better with a far-post volley.
Hayes became increasingly frustrated by a lack of discipline and a failure to clear the danger which put Holbeach under more pressure.
However, Bird’s tap-in finally broke the deadlock and he slotted in again to earn maximum points.
4-4-2: Drury; Harker, Tinkler, Braithwaite, A Jackson; Zuerner, Smith (sub Warfield 78 mins), Dougill, Bird; Leckie, Oliver. Subs not used: Davies, N Jackson, Jenkins, Simmons.
4-1-3-2: Trebes; Miles (sub Smith 81 mins), Gentle, J Ducket, Uttridge; Bream; R Ducket (sub Warwick 71 mins), Rogers, Draper; Brown, Lawless.
Bird (71 mins, 1-0); Bird (83 mins, 2-0).
Tinkler, Leckie, Bird, Bream (fouls).
Will Bird - terrific work-rate down both flanks, rewarded with two goals.
Walsall Wood (A) - Buildbase FA Vase second round, Saturday.