Champions Stevenage Borough finished their Blue Square Premier campaign with a 1-0 win that sets up opponents York City with a play-off semi final against Luton Town.
David Bridge's headed goal seized on a muddle between the Minstermen skipper Danny Parslow and keeper Josh Mimms.
Bridge was left unmarked as York failed to clear a cross and he simply guided the ball into an open goal.
It settled an uninspiring encounter as the visitors rested key players ahead of Thursday's first leg play-off.
Stevenage marked their thirtieth win of the season with a celebration on the pitch following the presentation of the Blue Square Premier trophy.
Rushden & Diamonds will face Oxford United in the play-off semi finals.
The final game of the regular campaign ended all-square against Luton Town at Nene Park as Mark Byrne cancelled out Tom Craddock's early opener.
Diamonds soon fell behind as Kevin Gallen fed Craddock who slotted low past Dale Roberts.
The leveller came when Paul Terry's pass was flicked on by Smith to Byrne who smashed a volley into the bottom corner beyond Mark Tyler.
Craddock wasted a golden chance, hit the post and went close again before the break.
Osano took centre stage for Diamonds with forward runs from left-back – having a couple of efforts and almost feeding Jefferson Louis for a clear-cut opportunity.
Craig Farrell nearly scored with his first touch as a second-half substitute and then a 20-yard free-kick was parried by Tyler.
Craddock missed the target again and Matthew Barnes-Homer lobbed over as the Diamonds defence came under pressure.
Kettering Town claimed sixth place in the table, despite defeat at the Raymond McEnhill Stadium against Salisbury City.
AFC Wimbledon's defeat at Gateshead meant the Poppies finished just outside the play-off places. But their preparations for the final game were not helped by an injury crisis.
Ian Roper and Darren Wrack were both ruled out and Marcus Kelly, despite taking part in the warm-up, didn't make it out of the dressing-room due to a hamstring problem.
It meant a big reshuffle for Lee Harper as youngster Mark Pryor was handed his full debut while James Dance started in the centre of midfield.
And it was Dance who had the first real chance when he got in behind the Salisbury defence but James Bittner was equal to his shot.
The hosts controlled the rest of the half and took the lead when Chris Shepherd fired low past Nathan Abbey after Darrell Clarke had helped on ChrisFlood's cross.
Jake Reid went close soon after and little was seen of the Poppies as an attacking force until stoppage time when Jean-Paul Marna saw a shot cleared off the line and Greg Taylor hit the rebound into the ground and over the bar.
Dance had a fine run from his own half soon after the break but his finish was weak as Bittner saved easily.
Most of the action was at the other end as Reid saw a shot blocked by John Dempster before Matty Tubbs' flick past Abbey was cleared by Taylor.
And Tubbs was denied his twenty-sixth league goal of the season when an offside flag stopped any celebrations after he found the net.
Shepherd sent another shot just wide and there was a cameo appearance for Salisbury boss Tommy Widdrington. And the home side's win was completed when Tubbs did get his goal with a terrific 20-yard strike into the roof of the net.
Jake Speight's hat trick was not enough for Mansfield Town to secure a final day victory as Kidderminster Harriers came back from three goals down to secure a thrilling 3-3 draw.
The Stags dominated the first half and Speight completed a first half hat trick to seemingly put the result beyond doubt for the hosts.
The striker opened the scoring after 17 minutes when he fired in from the edge of the penalty area and 7 minutes later he converted from close range.
Speight scored his third just before half time, once again with a typical striker's finish from close range to stun Harriers. But the visitors came out in a resurgent mood after the interval and Jack Byrne pulled a goal back from a Brian Smikle corner after 51 minutes.
Three minutes later Daryl Knights made it 3-2 and Chris McPhee completed the fightback with a 25-yard strike after 74 minutes to snatch a point.
Adam Marriott's brace was enough to give Cambridge United a 2-0 win away at Moss Lane against Altrincham, who saw a first half penalty saved by Simon Brown.
The U`s had the better of the early chances with Rory McAuley, Paul Carden and Scott Neilson all going close. But the Robins wasted a great opportunity to take the lead just before the half-hour mark when Brian Saah fouled Greg Young in the area and Colin Little saw his powerful penalty superbly punched away by Brown.
Altrincham began to force the issue in the second half but Cambridge broke the deadlock 15 minutes from time when Marriott slotted home his first of the afternoon.
And 2 minutes into injury-time he grabbed his and the visitors` second, courtesy of an Aiden Palmer assist.
Wes Baynes scored the only goal as Wrexham ended their season on a high with a win at Hayes & Yeading United.
Baynes netted after 23 minutes when he fired home from the edge of the area.
Adam Green and Craig Watkins squandered good early chances to give Hayes the lead before Baynes' strike. Johnny Hunt could have extended the away side's advantage before the break but he missed from 12 yards.
Mansour Assoumani missed from six yards and Declan Walker headed straight at Hayes keeper Clark Masters as the Dragons sought to extend their lead after the break.
Mark Jones also headed straight at the goalkeeper for visitors as Hayes failed to muster a shot on target in the second half.
Histon preserved their status after a last-minute Paul Jones own-goal gave them a 2-2 draw with Barrow at the Glassworld Stadium.
Histon took the lead after 27 minutes when Glen Southam calmly slotted home a penalty after Carlos Logan had brought down Lee Smith.
Charlie Sheringham could have extended the lead before the break but he was thwarted first by a block from Barrow defender Daniel Sheridan and then by a great save from Barrow keeper Stuart Tomlinson.
Barrow equalised 2 minutes after the break when Nick Chadwick headed home Simon Spender's cross before Simon Wiles drilled home from 20 yards to give the away side a 2-1 lead.
Histon pressured late on and Nathaniel Knight-Percival hit the bar before they got their equaliser when Jones headed into his own net 2 minutes into injury-time.
A penalty 8 minutes from time by Simon Weatherstone proved enough to keep Eastbourne Borough in the Blue Square Premier in a nail-biting game against Oxford United at Priory Lane.
Boro faced high-flying Oxford knowing a win should ensure their survival. But after Luke Rooney struck the underside of the bar and Weatherstone twice came close it looked like Boro could be dropping down.
But when Mark Creighton handled Luke Benjamin's shot in the Oxford area Weatherstone made sure from the spot to ensure the Sussex club a third successive season in the Blue Square Premier.
Daryl Clare's goal was enough to clinch a 1-0 victory for Gateshead against AFC Wimbledon and send Forest Green Rovers down on goal difference.
Clare gave the home side a dream start after just 4 minutes, scoring from close range after Craig Baxter's cross.
He could have doubled the lead on the stroke of half time had he been more accurate with an effort he blazed over the bar.
The Dons had numerous chances to score through, especially through Danny Kedwell who was guilty of missing a host of opportunities in both halves.
Both Baxter and Clare could have doubled the lead but it did not matter as Gateshead survived by the skin of their teeth.
Forest Green were relegated in dramatic fashion as already-doomed Grays Athletic fought back to claim victory.
Following an uneventful first half, Reece Styche was brought down in the area on 66 minutes and David Brown converted the penalty to give Forest Green the lead.
Despite piling on the pressure Forest Green could not finish the game off and Alex Osborn drew Grays level with a well taken finish 15 minutes from time.
Alsseny Cissoko headed home a late corner to send Forest Green down.
Ebbsfleet United were also relegated, despite a 4-3 win at The Lamb against Tamworth.
A late Scott Ginty brace won the game for the visitors. With the score at 3-2, the substitute levelled when he turned and fired the ball home from 12 yards with 13 minutes remaining.
Three minutes later the striker won it with a volley that flew into the top corner.
Tamworth had taken the lead after 11 minutes through Iyseden Christie, who made space in the penalty area and fired the ball into the bottom corner.
But a minute later Ebbsfleet were back on level terms through Mango Vieria, who met an in-swinging Michael West corner from the left to head into the top corner.
Fleet then took the lead after 38 minutes through Ricky Shakes who found space in the penalty area and fired home from 12 yards.
Their lead didn't last long as Michael Wylde levelled a minute later, the defender nipping in at the near post to head Neil MacKenzie's cross past Lance Cronin in the visitors goal.
Brad Pritchard put Tamworth back in front after 58 minutes with a stunning 25-yard volley that flew past Cronin before Ginty struck late on.
