The 18-year-old lost on points to Jordan Flynn (Hoddesdon) in their English title eliminator at the Irish Centre in Birmingham and Edwin Cleary said it was another decision that left his coaches scratching their heads.
“We thought he’d won the second and dominated the third,” said Cleary.
“Having a point taken away in the third probably didn’t help.
“The third was Danny’s strongest round with Flynn feeling the pace and at times hanging on.”
Quartermaine is just two months into his senior career and having suffered back-to-back points defeats in eliminators, Cleary said it was important he did not get too disheartened.
“He’s definitely not losing these fights he’s just not getting the decisions,” added Cleary.
“In the amateur game over three rounds it’s sometimes very hard to separate two evenly-matched boxers.
“But with a couple of tweaks here and there I’m sure Danny will start getting the decisions.”
Quartermaine’s next fight will be on Cleary’s Gym’s home show at the Trident Centre on March 12 when he take on 2015 senior elite ABA runner-up Jack Wood (Wednesbury).
The evening also features Lewis Williams, who takes on two-time national champion Ryan Butler (Berry Boys) and will see the return to action of Sean Greenfield, Michael Jephcott and Ricky Attwell after lengthy spells out of the ring.
Meanwhile, Josh Finch is fighting on Sunday in Donnington in the Midlands junior final at 52kg against Darren Ward (Wednesbury ABC).
“It’s exiting times at Clearys boxing gym,” added Cleary. “It’s great to see the boxers we are producing right up there with the best.”