Bristol Rovers crashed out of the FA Cup in the First Round at the hands of Chesham United.
Ryan Blake's long range effort was enough to see Chesham into Monday's Second Round draw.
Darrell Clarke made two changes to this side that won at Cambridge United last week bringing Daniel Leadbitter and Matty Taylor into the starting line-up at the expense of James Clarke and Jermaine Easter who took up their spots among the substitutes.
The visitors started positively and Lee Mansell fouled Brad Wadkins early on allowing Chesham skipper Toby Little a strike at goal from the resulting free kick. Little took it direct but failed to trouble Lee Nicholls in the Rovers goal.
Rovers had a few speculative efforts in the opening 20 minutes as Matty Taylor, Ellis Harrison and Billy Bodin each had strikes that failed to test Shane Gore.
It was Chesham who were presented with a real opportunity to take the lead as Tom Lockyer was judged to have fouled Brad Williams in the penalty area with referee Andy Davies pointing to the spot.
Dave Pearce stepped up to take the penalty and drove the ball low with pace but Lee Nicholls was able to react well getting down low to keep the game goalless.
Darrell Clarke's side began to click through the gears as Matty Taylor continued to find more and more space but two of his efforts were blocked by Ashley Smith and George Fenton respectively.
Both sides came out for the second period by Rovers looked a lot more fired up and could have taken the lead five minutes into the half as Matty Taylor picked up the ball, advanced into the penalty area, twisting and turning before his eventual shot was blocked by a pair of Chesham bodies.
Moments later Billy Bodin pulled the ball out of the sky from a Rovers corner but blasted his right footed effort high and wide of the United goal.
The home sides superior fitness began to tell in the second period as Chesham conceded several corners in a row with the best effort coming as Tom Lockyer got his head on a Jake Gosling corner but headed narrowly over.
Rovers continued to press for the opener but shots from Lee Mansell and Billy Bodin forced two good saves from Shane Gore just before the hour mark.
With things not going his sides way, Darrell Clarke decided to make two changes on the hour mark bringing on Chris Lines and Jermaine Easter for Lee Mansell and Matty Taylor and Easter was involved in the action straight away.
Billy Bodin was able to pick out Easter in the penalty area before firing a shot at goal. Shane Gore made a decent save but back into the path of Easter who squared the ball for Ellis Harrison who could only fire over from close range.
With just over 20 minutes of the game remaining Chesham United made their first substitution as Barry Hayles replaced Dave Pearce. Hayles of course a former Rovers man scoring around a goal every other game during his spell in the blue and white quarters.
Moments later the Evo-Stik Southern Premier side took the lead as Lee Nicholls mis-read a long range effort from Ryan Blake and the ball snuck into the goal under the on-loan Wigan Athletic man.
Rovers then threw the kitchen sink at the non-league side with the best chance of the spell coming from Lee Brown's corner as Ellis Harrison timed his run well but was denied by a fantastic reaction save by Shane Gore.
Gore proved to be the difference in the closing stages denying Jermaine Easter on numerous occasions ensuring Chesham advanced into Monday night's Second Round draw.
Up next for Rovers is the trip to Roots Hall to take on Southend United in the Johnstone's Paint Trophy before entertaining Carlisle United at the Mem in SkyBet League Two action next weekend.
Rovers: Nicholls; Leadbitter (J. Clarke - 71), Lockyer, McChrystal (C), Brown; Bodin, Sinclair, Mansell (Lines - 61), Gosling; Harrison, Taylor (Easter - 61).
Unused Substitutes: Mildenhall (GK), Parkes, Montano, Lucas.
Chesham: Gore; Smith, Fenton, Beasant, Ujah, Taylor (Hamilton-Forbes - 90), Pearce (Hayles - 71), Youngs, Blake (Casey - 86), Wadkins, Little (C).
Unused Substitutes: Legg (GK), Fongho, Fletcher, Woodcock.