Richard Wood knows Rotherham will not be a force at home in the Championship if their defensive lapses on continue.
The Millers slipped to a 3-2 defeat to struggling Hull on Tuesday in a game they would have earmarked as one to win.
But there was some shoddy defending in the build-up to all three of Hull's goals, which meant Wood's opener and a late Jamie Proctor strike counted for nothing.
Any chance that Paul Warne's men will have of surviving in the second tier this year is likely to be down to how they perform in their own backyard and Wood says they can ill-afford to be handing freebies out.
The defender said: “It was very disappointing, gifting them goals and you can't do it at this level and expect to win.
“In the last half an hour we gave it a good go, but you can't score four goals at home to win. The goals we gave away were disappointing.”
Despite Hull's terrible start to the campaign, boss Warne is not viewing the loss as an opportunity missed.
The Tigers arrived in South Yorkshire without a win in their first three games and the mood at the club was low after they were booed by their own fans at the weekend.
Warne, though, says the game should not have been seen as a gimme just because of Hull's position coming into the clash.
Warne told the Star: “I want to win everything so I am disappointed, but I don't believe in all that poop.
“They played really well against Aston Villa for 60 minutes, I went and watched it, they were more than competitive against Sheffield Wednesday and conceded a late penalty, and they lost by one goal to Blackburn so it is not like they have been the whipping boys.
“Is it a massive shock that Hull beat us? I don't know, that is for you lot to write.
“I just think that if we had absolutely been at our best and been error-free on the pitch we would have had enough to win the game.”
The Millers are holding an open day on Friday, where Warne's squad will train at the AESSEAL New York Stadium at 11am and then be available to supporters for a meet-and-greet session from 1.30pm.
Doors at the stadium open from 10am.