"I retire today not because I don't feel I can go out there and still play the game at a very high level," Merriman wrote, "I am retiring because I want to retire on my own terms and leave while I know I can still physically play the game."
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The evidence suggests Merriman's ability to play at a high level evaporated after he had surgery to repair a damaged posterior cruciate ligament and lateral collateral ligament in his left knee in 2008.
The artist formerly known as "Lights Out" quickly established himself as one of the NFL's most feared pass rushers with 39.5 sacks, three Pro Bowl berths in his first three seasons and a 2006 first-team All-Pro selection. Since then, though, Merriman has collected just six sacks while playing in 33 of 80 games across five seasons.
Detractors might note that Merriman's decline began with a positive test and subsequent suspension for the anabolic steroid Nandrolone back in 2006.
Once regarded among the brightest of the NFL's young stars, Merriman will hang up his spikes with 45.5 career sacks and just two months shy of his 29th birthday. Look for a career requiem on future "What Could Have Been" episodes airing on NFL Network.