Hill’s Eastleigh are without three senior centre-backs – Aaron Pierre, Niall Maher and Lloyd Humphries – while two more defenders are away with Wales under-21s.
Archie Harris, who has recently played at centre-back, and Luey Giles joined up with the Wales squad after Saturday’s 1-0 defeat at Hartlepool, despite Eastleigh requesting a delay.
With Temi Eweka the only other option, Hill “pestered” a lot of people before deciding to sign Saints academy defender Moore until the end of the season.
The 19 year old is yet to make his senior debut, with his first-team experience limited to two games on the bench, including one against Arsenal.
But he will need to adapt quickly before making his senior bow in Eastleigh’s massive game against fellow National League strugglers Sutton United.
“In the last few weeks, we’ve lost Aaron Pierre, we’ve lost Niall, we’ve lost Lloydy. When you are without three players like that, we had to do something,” Hill explained.
“I made a lot of phone calls over the weekend, a lot on Friday night, and pestered a lot of people on Sunday morning.
“We decided to take Jayden from Southampton. He is going to be thrown right in at the deep end. We will see where he gets us.
“Right now, there is no other choice at centre-half. I’m too old, and I’m too slow, so I cannot play there,” Hill quipped.