Tulips boss Dave Frecklington insists his side can forget about winning league titles if they continue to let victories slip through their grasp.
Spalding saw a 1-0 lead evaporate on Tuesday night as visiting AFC Rushden and Diamonds struck twice in the final 15 minutes despite being reduced to 10 men following the dismissal of Rory Winters.
It was the third time this season that the Tulips had lost the lead when playing against ten men and saw them miss out on the chance to go back to the top of the EvoStik Division One South.
And boss Frecklington believes Spalding’s inability to see out a game against ten men is something that he and his management team need to urgently address.
He said: “I can’t believe we lost the game but, if you don’t take your chances, you leave yourselves wide open.
“It’s a massive missed opportunity. It might be a big statement, but our mentality is weak.
“I will never question our attitude and effort, but sometimes that is not enough.
“We should be experienced enough to see games out, but we’re letting teams back in and giving them a lift.
“We have now lost back-to-back home games which is disappointing.
“We are not going to win the league like that and I’ve told the lads to not think about winning league titles.
“It isn’t just a blip. We have let too many crucial points slip away which isn’t good enough.
“It shows though that when a club like Rushden celebrate beating you like they’ve won the league that we’re doing something right.
“But we have to address seeing games out because we have played well, asked questions of them and created chances.
“We didn’t put our chances away though and we’ve been punished for that.
“We’ve then conceded two sloppy goals in the last ten minutes which has absolutely snapped us.”
Spalding handed a debut to the returning Mitch Griffiths who went straight into the Tulips starting line-up.
Rushden were handed the best opportunity of the early exchanges as Jordan Lemon allowed a through ball to roll under his foot but, with just goalkeeper Michael Duggan to beat, Nic Evangelinos blazed wide.
Jack Wightwick, on his home debut, offered Spalding’s best attacking threat as he twice flashed shots wide of the visitors’ goal.
Duggan then had to produce an excellent athletic save to keep out a Liam Dolman free-kick which was destined for the top corner of the home net.
Spalding took the lead three minutes before half-time when Nathan Whitehead rose highest to head home the opening goal.
Bradley Wells missed a couple of decent opportunities to increase Spalding’s lead after the break while Wightwick rattled the crossbar with a cracking effort.
The lively Wightwick then wriggled clear of several tackles only to be denied by a sprawling save from visiting goalkeeper Ben Heath who was making his debut in the Diamonds goal.
The visitors were then reduced to 10 men when Winters was dismissed for a second booking, but the sending off seemed to spark Diamonds into life.
After Heath had produced a smart stop to keep out a Whitehead piledriver, Rushden broke and, as Spalding struggled to clear their lines, Richard Bunting picked up the loose ball before firing home from 20 yards.
Rushden now had the initiative and took the lead with five minutes remaining as Jack Ashton headed home.
Spalding still continued to create openings and Wightwick was again denied by Heath whose smart injury time stop preserved the points for Rushden.
Tulips: Duggan, Lemon, Walker, Varley, Stainfield, Gatter, Griffiths (Higginson), Whitehead, Wells, Wightwick (Wright), Acar. Not used: Hamilton, Field, Downey.
Attendance: 292.
The Tulips are at home again on Saturday when Newcastle Town are the visitors. The two sides are currently locked on 30 points, one adrift of leaders Shaw Lane.