Gomez was out for a lengthy period when Klopp first came to the club in 2015.
He was worried he'd lose his squad place, but Klopp told him not to worry and to focus on his recovery.
Gomez told Sky Sports: "I got my scan for my ACL the day he came in.
"Obviously at that point in time as a young player, I remember being on that camp when it got announced that he was going to be our manager and I think I was 18 at the time, you are eager to come back and impress.
"And you are thinking, 'does he know about me? What does he think of me? Am I going to get a chance?' So obviously at that point, I was devastated at the timing being so bad, but straight away he spoke to me.
"I remember getting the results in the doctor's office.
"And as soon as I got the results he came in and spoke to me and just said, 'I'm here for you and I'll be waiting for you,' that sort of thing.
"Those words stuck with me throughout my whole rehab, which obviously was a tough one. I had my setbacks, but he was always communicating with me.
"Then coming back - he himself had an ACL injury when he was playing and I think that helped him relate and understand what I was going through.
"And not just once I got back, but just the process and understanding that I myself was still young at the time and that even when I thought I was ready, I was not ready and he knew when I was ready.
"He was massive for me and since then I have had numerous difficult injuries and he was always understanding and communicating with me.
"Thankfully I have had a longer period now where I have been able to get games under my belt and play consistently and I am thankful that he showed that patience in me, because throughout that time, you never know if you will get a chance again.
"And he showed faith in me, so I will forever be in his debt for that."