Pepsi and Coke are at it again, this time taking false ad claims to the courts.

Gatorade, a PepsiCo brand, filed a lawsuit Monday against Powerade, made by Coca-Cola, in U.S. District Court. The suit asks that an ad campaign be halted that Pepsi claims in false and deceptive, according to news reports.

The case centers on a TV ad for Powerade Option that shows a horse-drawn cart race between two farmers. One cart carries 10 bales of hay and the other carries 50. The cart with 10 bales easily beats the other and the ad touts that Powerade has 10 calories versus Gatorade’s 50 calories.

The suit claims that the message to consumers is that Powerade’s fewer calories make you go faster cannot be substantiated, the reports said.

Coca-Cola said that Gatorade has no research to prove the allegations.

“Our ads tell the truth and we stand by it, Powerade Option has fewer calories than Gatorade,” said Dan Schafer, a spokesperson for Coca-Cola.

The ads debuted last week during the National Collegiate Athletic Association men’s basketball tournament.

Officials at Pepsi could not be reached for comment.

Last August, the National Advertising Division of the Better Business Bureau took a case brought by Gatorade against Powerade related to comparative TV ads by Powerade that said, that “No leading sports beverage provides…faster absorption than Powerade” among other issues. NAD recommended that the commercials be modified to avoid conveying an unsupported implied message that drinking Powerade will increase strength.

“Our ad fulfills the NAD decision and clearly states that calories equal carbohydrate energy,” Schafer. Gatorade has no research to prove their allegations.