Chris Messina Thought Kaley Cuoco Was Going to Give Birth on Set "at Any Minute"

As onscreen spouses, Kaley Cuoco and Chris Messina are experts at handling chaos. In real life, the "Based on a True Story" costars and friends also know how to keep each other on their toes, especially when it comes to friendly competitions. Speaking with POPSUGAR Creative Producer Gabrielle Bailenson, the pair opened up about their hypothetical true-crime alibis, guilty-pleasure purchases, and who would win in a tennis match.

"She would just make fun of me," Messina says of Cuoco, who has been playing tennis since she was 3. "I kind of made sure [Kaley] wasn't around when I was playing tennis 'cause I would've been so embarrassed," Messina adds. Growing up, Cuoco was a nationally ranked amateur tennis player in Southern California. Even though she switched to acting full time at 16 years old, the former tennis star hasn't lost her competitive edge. "I'm pretty savage when I get out there," she says.

In fact, on the last day of shooting, Cuoco — who was nine months pregnant with her daughter, Matilda, at the time — took a break in between filming to challenge showrunner Craig Rosenberg to a match. "I said, 'I'm gonna play tennis today.' [Chris] goes, 'Please don't do that. You might have this baby.' I'm like, 'We'll be fine.' He was freaking out. He was very concerned." Still, Cuoco stepped on the court with confidence. "It was a sight to be seen," she says. "There were a lot of spectators probably wondering what the hell I was doing out there. Chris was freaking out, running around being like, 'Do you need water? Don't run. Don't move!'"

In his defense, Messina says, "At the end of the show, we thought, 'At any minute, maybe she'll have a baby.'" As for the final score, he adds, "She kicked [Craig's] ass." While Cuoco's tennis game is unmatched, maybe she and Messina can convince the writers to write a pickleball competition into the script if the series gets picked up for a second season.

Watch Cuoco and Messina's banter-filled interview above to hear more about their offscreen relationship, and catch "Based on a True Story" on Peacock on June 8.