Delph has suffered a number of major injury setbacks since his £6million move from Leeds four years ago, and admits he is known as "Dr. Delph" around the training ground.
But he has impressed in recent weeks, although his 10th booking of the season against Manchester City will rule him out of the two relegation clashes with Reading and QPR.
Delph said: "This is my first season that I've actually been fully fit. I've had some terrible injuries. This has been my best spell since I've been here.
"I've been here a long time and, for me, it is personally about paying back the faith the chairman has put in me and also the faith the manager has put in me.
"You see some people buy a player, they don't hit the levels that they should do and, next thing you know, they are out of the door.
"I have massive respect for the chairman because what he has done for me is fantastic.
"He's been supportive and I have been injured a lot. He's been one of the main figures that has been really positive towards me and told me to keep going.
"He is a really humble, nice man and he loves the football club. He invested money in me.
"It's about repaying the fans as well because they have shown me tremendous patience. It's nice to be fit!"
Delph said: "I have been injured for three years solid. I have always had something.
"I ruptured my anterior cruciate ligament, injured my lateral meniscus, I had medial damage, then I came back from that and had another injury with a medial ligament.
"Then I had an ankle injury, I came back and got a knee injury. I could go on all day. I've become known as Dr. Delph! Whenever anyone gets injured, the lads seem to look at me.
"I think I have told a few of the lads when they have rolled their ankles this season 'honestly lads, I think it is your anterior ligament.' They've gone for a scan and said 'you were right'.
"I've had a lot of injuries and, thanks to the medical staff and people around me, I've been lucky enough to have some great support. I've managed to get stronger."
Delph said: "I still don't feel as sharp as when I came here and there are loads of areas I need to work on.
"I feel like I am getting stronger, finding a tiny bit of form and just want to do my best for the club."