A new pair of kicks weren't the only upgrade LeBron James was unveiling Tuesday at Nike's headquarters in Portland.

At least that's what dozens of skeptical observers claimed in a flurry of Twitter posts after the four-time NBA MVP's presentation of his new LeBron 12s.

James' hairline, which has been receding for years, was mysteriously restored. And people took notice:

Lots of Twitter users took to social media with their theories, many of which revolved around hair plugs.

James' hairline has been the subject of jokes by fans, other players and himself, such this tweet from 2011:

Despite calls from former NBA greats to follow in the footsteps of Kobe Bryant and Michael Jordan and shave his head, James has insisted on keeping what is left of his hair.

James changed his look this summer, cutting some weight as he prepares to enter his 30s. Perhaps the restored hairline is part of his new look.

If he indeed purchased hair plugs, James wouldn't be the only high profile athlete to do so in recent years. British soccer star Wayne Rooney has received not one but two hair transplants.

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