Venus Williams reveals why you'll 'never' see her acting

There's a reason why you've never seen Venus Williams on television playing any role other than herself.

The 7-time grand slam champion had to memorize some lines to recite on camera for her upcoming appearance at a new augmented reality game, The American Express Super Rally fan activation, set to debut at this year's US Open, and it reminded her why she has no interest in acting.

"I get really nervous with lines," Williams admitted in an exclusive interview with AOL's Gibson Johns. "I don’t mind getting on camera and swinging my racket, but with lines, I’m like, ‘That might not be great! I’m not an actress!’"

Venus' revelation differs greatly from her younger sister, Serena's, interests: Serena famously had an affinity for acting earlier in her career, and she appeared in a string of television shows like "E.R." back in 2004. Instead, Venus has always put her non-tennis energy into her design businesses.

"I think it came out okay," she added with a laugh. "That’s why you never see me in anything on-camera or on any TV shows. I know I’m athlete. I’m going to stay in design and stay on the tennis court."

This year marks the third consecutive year that Williams has partnered with American Express ahead of the US Open. The company, which is also offering new Amex Bands to Card Members that allow for contactless purchases throughout the tournament, has supported the all-time great "professionally and personally" since she got her first American Express card back in 1995, at the age of 15.

Though Venus is a self-described "simple person," she did admit to AOL that she has a weakness for jewelry -- well, actually, shopping in general -- but she still won't purchase something if she thinks it's overpriced.

"I do love clothes, jewelry, shoes and shopping, but I have to watch myself," she laughed. "I can literally start salivating in a store and they'll be like, 'Are you okay, ma'am?' But I think I always want to feel like I'm being treated fairly. Even if something isn't expensive, if I don't feel like it's fair, then I won't buy it."

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When it comes to her interior design business V Starr Interiors and her apparel brand EleVen, Williams is similarly frugal, especially when it comes to things like travel. As she told us, it's more important to splurge on marketing her brands, as well as getting the best possible team around her.

"I definitely try to save on travel expenses, that’s important," she explained. "You want to reinvest into the business, so we don’t want any money going off-book for no reason. I do invest in branding and marketing, which is extremely important. Also investing in my people and my team is necessary."

As for preparing for the US Open, which starts on Monday, Williams said that she recently started to take a day off ahead of big events in order to adequately rest her body for the onslaught of on-court time coming her way.

"I am always making changes, and recently I started taking one day off," she said of her pre-tournament rituals. "I think that helps! The day off might be five days before the event stats, but it's just to be able to rest your body and come back stronger. It’s a little bit opposite from working harder or doing more exercises, but I’ve worked hard and done those exercises already, so now it’s about pacing yourself and being optimally ready for the big push."