The opening days of Indianapolis 500 practice have already delivered a major story line, and not the kind Chevrolet was hoping for. After just two sessions at Indianapolis Motor Speedway, Chevy has been forced to replace three engines—raising eyebrows and concerns across the paddock.

With 18 of the 33 cars in this year's race carrying Chevrolet power, reliability is paramount. But on Tuesday, the first day of practice, Ed Carpenter Racing's Ed Carpenter and Team Penske's Scott McLaughlin both had their engines swapped. A Chevrolet spokesperson noted the issues were "not the same," but the pattern continued Wednesday when Carpenter's teammate, Alexander Rossi, also had his engine changed and sent back to GM's Detroit headquarters.

"I am concerned," Rossi admitted Thursday morning. "It's not only Ed and I, there's been two others as well. We don't have the full information—are they the same failures? Is it something batch-related? All I know is Chevy is just as focused on making sure we can have a strong month. We know we're the engine to beat, so hopefully the bad luck's out of the way."

For fans and gear enthusiasts alike, engine reliability is the backbone of any great race—and a reminder that even the best technology faces challenges under the intense pressure of Indy. As practice continues, all eyes will be on Chevy's response and whether these early hiccups are just a blip or a sign of bigger trouble ahead.