Cooper quit nearly three weeks ago after Pools had slipped to the bottom of the table with only one league win all season and former Hull boss Phil Brown was quickly installed as a hot tip to replace him.
Brown had publicly declared he wanted the job and both he and assistant Brian Horton had watched the club's reserves on Monday night, but it was Hughes, 48, who was unveiled as their new manager on 24 hours later.
Green, who confirmed Sven Goran Eriksson had applied for the job, said: "We were in a situation where we were just assessing everything. We had never offered anybody the job, we just looked at the candidates, going through the normal process and there were always two or three targets that we looked at because you wonder whether they would be available and there's terms and conditions you've got to look at, but the man we wanted was this guy, it honestly was.
"The press picked up on Phil Brown coming and they shot themselves in the foot with it really because we'd already spoken to John on several occasions and as you can see, you know why we chose him. He's dynamic. He's the man.
"A lot of clubs in our situation have to weigh things up. Do you want an experienced guy, a young up-and-coming guy, that's always a gamble, but we thought we could combine both here and use his experience, while he's now a young and up-and-coming manager in England. The Scottish managers all seem to want to get down here and prove themselves and John said to me he would make a go of it in England. He said he would not leave here until he had been a success."