Nick Viall's bachelorettes are already envisioning themselves falling in love with The Bachelor star several episodes into Season 21, but they shouldn't anticipate hearing "I love you" back any time soon.

"I only want to say, 'I love you,' to one more person," Viall said while filming The Bachelor, according to Entertainment Tonight.

"So I am really kind of holding my cards close when it comes to that."

Viall said those important three words to both Andi Dorfman and Kaitlyn Bristowe on their respective seasons of The Bachelorette, which both ended in heartbreak for the 36-year-old former software salesman from Wisconsin.

Viall finished as the runner-up both times, losing the women of his dreams to other men he didn't get along with. (Dorfman and winner Josh Murray split shortly after he proposed, but Bristowe is still engaged to Shawn Booth, whom she gave her final rose to).

When Viall appeared on Season 3 of Bachelor in Paradise this past summer, he was very close to falling in love with Jennifer Saviano.

However, he didn't give his heart away and later admitted he was probably closed off due to fear he may become a joke, like some sort of Trivial Pursuit question.

Viall therefore intended to put great thought into whom he'd say "the L word" to again. He went into The Bachelor very careful not to express himself too early.

Before embarking on his first one-on-one date of the season with Rachel Lindsay in New Orleans -- which viewers will see in the upcoming January 30 episode -- Viall explained to ET that he was "certainly not in love at this point."

"But I think coming into this, I didn't know if this was really going to work... I was really worried because one thing I promised myself is that I wouldn't [just] get engaged to whatever girl ended up last," Viall confessed.

"But I am more optimistic now, because there are some great women... I want to make sure that if I am lucky enough to [fall in love] with someone here, that it is something I would 100% be certain of."