Robin van Roosmalen remembers the first time he knew, without question, he eventually had to compete in mixed martial arts.
It's a pretty simple story, really. An easy memory to recall. The veteran kickboxer knew he had to compete in MMA the first time he hit pads with 4-ounce gloves.
"I didn't really like the game at first, the wrestling between standup," van Roosmalen told ESPN. "But the small gloves, that's what really drew me to it. Sometimes in training, I'll get lazy with the big gloves. With small gloves, you can't do that. You don't want to get hit. It's a whole different game.
"I was excited and scared at the same time. I put those smaller gloves on and said, 'Wow. I need to hit somebody with these.'"
Earlier this month, van Roosmalen, the only two-weight champion in Glory kickboxing history, announced his departure from the ring in order to pursue MMA full time. The 29-year-old will compete at 145 pounds.
Originally from the Netherlands, now fighting out of Hard Knocks 365 in Fort Lauderdale, Florida, van Roosmalen hasn't signed with an MMA promotion yet, but says a deal could be in place before the end of the year.
"I've been training MMA for five years," van Roosmalen said. "[Coach Henri Hooft's] gym is the only gym I've trained MMA. When I'm home, I normally just do kickboxing and boxing.
"I've been working with all the guys. [Former UFC featherweight] Sean Soriano is a really good friend of mine. [Michael] Chandler, [Michael] Johnson, [Nik] Lentz -- all of them. My ground game is still a work in progress. I'm not on their level -- but they're not on my level in the standup."
Several notable kickboxers have transitioned into MMA in recent years, including the UFC's Gokhan Saki and Israel Adesanya. Adesanya in particular has done very well. The New Zealand native is scheduled to face Anderson Silva at UFC 234 in February.
Van Roosmalen -- who has a 2-0 MMA record, with knockout wins in 2016 and 2017 -- believes he is prepared for similar success.
"I want to be the best, in the best promotion -- so I prefer to sign with the UFC," van Roosmalen said. "I think Adesanya was a great kickboxer, but he was never a Glory champion. I've been a Glory champion in two divisions. I think my standup is better, but that's not to say anything bad about him. He is a great fighter.
"I think some kickboxers who try to transition to MMA, in their minds, it's still kickboxing. They don't understand MMA. Adesanya is very good at understanding the MMA game. It took me a couple years to do that as well. But right now, I'm mixing it up good in MMA."
Van Roosmalen doesn't know what to expect in terms of salary out of the gate, but knows there is a higher ceiling of pay in MMA. He plans on leaving a mark on his new sport similar to the one he left in kickboxing. And if he's successful in that, the money will come.
"I got paid enough in kickboxing, but not what it is MMA-wise," van Roosmalen said. "If I become a two-weight division in MMA, I'll be a millionaire."