"Two goals from set pieces, that just kills you, doesn't it," he said. "We've worked hard, got back into the game with an equaliser after the break, then we lose two goals within a few minutes. We shouldn't have conceded those free kicks but equally we didn't defend them properly.
"The lads were ball watching for Miramar's second, you can't just switch off against good sides, they'll punish you, and that's what's happened there."
Nor was Hastings happy about how his side performed in the first half, conceding a goal after 14 minutes, veteran Wiremu Patrick seemingly miss-hitting his shot and fooling Underhill.
"We gave away the ball, then two of our midfielders run into the referee so they can't track back, it was just a comedy of misfortune if you like."
But such a goal shouldn't detract from the lacklustre nature of that half, and other than Bill Robertson, with his tannoy-style questioning of the referee and attempts to motivate his team-mates, the edge was lacking.
"Robertson cares, everyone should be passionate out there, but ... I think some took a while to be passionate," said Hastings.
He would presumably not have been talking about Underhill who made a brilliantly athletic save to stop Paul Ryder's pinpoint header, and a few minutes later parried Pat Fleming's deft flick round the post. And Hastings also hailed Enrique Dondiz for his tireless energy.
On 53 minutes, Andy Bevin provided a fine cross for Rudi Bauerfiend to squeeze the ball past Phil Imray in the Miramar goal. But once Miramar scored twice in quick succession Napier lost their impetus until near the end when Fane Morgan's shot was saved by Imray, and Danny Wilson's free-kick hit the post. Deep into injury time Argentinean Dondiz scored from close range, but it was too late to salvage something from the game.
Napier now look to progress in the Chatham Cup this afternoon when they host Capital Premier side Wainuiomata at Park Island.
While their league defence seems beyond them, there was some good news from Wairarapa, who ended Olympic's seven-game winning run with a 2-0 home win.
In other matches, Lower Hutt City beat Tawa 1-0 at home, Western Suburbs and Petone drew 1-all in Porirua, and Upper Hutt City beat Wellington Utd 3-1. Despite their loss, Olympic still head the league by a point, ahead of Miramar.