2023 was a bad year for Elon Musk. Even before his antisemitic tirade, the billionaire’s mounting failures at X/Twitter took Musk from media darling to a near-laughing stock. His bid to take SpaceX pubic is faltering after its satellite internet business Starlink brought in just $1.4 billion of the $12 billion Musk projected. Now it seems Tesla is falling behind. According to Bloomberg, a Chinese automaker called BYD Co. is about to pass Tesla as the world’s most popular manufacturer of electric cars.

BYD isn’t that well known on the world stage, but that may change in the near future. In recent years, China moved in on Japan as a new rival for the world’s leading consumer car exporter, and BYD is one of the fastest-growing companies in China’s booming industry. Current projections say BYD will overtake Tesla’s top spot for electric car sales within the next few months.

It marks a turning point in a decade-long competition between billionaires. BYD CEO Wang Chuanfu set his sights on Tesla in the early days of his company’s foray into the electric car business, bolstered by major investment from Warren Buffet’s firm Berkshire Hathaway. Musk ridiculed the Chinese company in a recently surfaced TV interview, but today it’s clear that BYD is a legitimate threat to his empire.

Tesla is already reeling from a stretch of difficult road. In just the past few months, investors called for Musk’s resignation from Tesla after he shared his feelings about Jews, the California Department of Motor Vehicles charged the company with fraud over the claim that its cars are fully autonomous (they’re not), and the CEO seemed to nearly break out in tears on a disastrous earnings call, during which he said: “we dug our own grave with the Cybertruck.” Musk’s antics even started to turn longtime fans who based their entire internet presence on supporting him.

It won’t be easy for BYD to expand its domestic success with electric car sales overseas, particularly in the US where its vehicles are essentially nonexistent. But if the company comes anywhere close, Musk is in serious trouble.