ALLEN PARK -- Plenty of athletes have nicknames, but Detroit Lions wide receiver Calvin Johnson is blessed with one of the best.

Johnson, known as Megatron, can thank former teammate Roy Williams for the moniker.

"I've never seen anything like him," Williams said in Sept., 2007, Johnson's rookie season. "He's a big, strong, physical, fast guy. We call him Megatron."

Megatron, for those who might not know, is a robot from the Transformers comic book, cartoon, and most recently, blockbuster movie, franchise.

The nickname was intended to be a play off of Johnson's incredible size and speed. At 6-foot-5, 235 pounds, with a sub 4.4 second 40-yard-dash time, no wide receiver comes close to matching the combination.

The typically humble Johnson seems to be enjoying the nickname. As he answered reporters questions after Monday night's game, he pulled out and put on a new hat, one featuring the logo of the Decepticons, the group of evil Transformers led by Megatron.

"A little Megatron, you know, you got to like that," Johnson said when asked about the hat. "I just found it at the store."

If you're looking to complete the Calvin Johnson look, you can own the cap for $35.