The injury occurred during the afternoon session at Indianapolis' training camp. Heyward-Bey was then taking to the training tent at Anderson University and watched the rest of practice with the knee wrapped in ice.
The timing couldn't be worse. Heyward-Bey, who never lived up to the hype of being a first-round pick in Oakland, had played well during the first week of camp and starting to find a home with his new teammates.
"He's growing, he's getting better and better each week," Reggie Wayne said Friday. "He can be a freak of nature, he really can be. So I'm here to help him in whatever way I can. "
Indianapolis signed the free agent in April, hoping Heyward-Bey could emerge as a consistent deep threat.
He didn't play like one in Oakland. The seventh overall pick in 2009 caught just 41 passes for 606 yards as a rookie, then had 64 receptions for 975 yards in 2010. Both were career-highs. Over the past two seasons, though, Heyward-Bey had a combined total of 35 passes for 490 yards and two TDs.
Though Indy appeared set with Wayne, the perennial Pro-Bowler, and T.Y. Hilton, one of the league's top rookies, as their top two receivers, they still brought in Heyward-Bey with hopes that a change of scenery - and offense - would jump-start his career.
Now, if he misses any significant time, it could leave the Colts with an early hole.
Last year's second starter, Donnie Avery, left in free agency, and LaVon Brazill, who was supposed to have an increased role this season without Avery, was suspended for the first four regular-season games because of a violation of the NFL's substance-abuse policy.
Indy also lost rookie running back Dan Moore during the afternoon workout with a right shoulder injury. Team officials said he sprained the AC joint.
Pro Bowl safety Antoine Bethea did return to the field Sunday after missing four days of workouts so he could attend the birth of his daughter, who spent four nights in the Neo-natal intensive care unit. Saturday was an off-day for the Colts.
"They're doing good," Bethea said. "Baby came home on Friday so everything is good on the home front."
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