4. Pierre Garcon
The Colts spent a sixth-round pick on Pierre Garcon in 2008 and by his second year in the NFL, he was one of Peyton Manning's favorite weapons. Garcon had 765 receiving yards and four touchdowns during that 2009 season.
Garcon's best year in Indianapolis came in 2011 when he had 947 yards and six touchdowns. Unfortunately, that was his final year with the Colts but he amassed 2,519 receiving yards and 16 touchdowns in his four years in Indy.
Garcon didn't play for the Colts for his entire career and had some massive seasons while in D.C. Despite not hearing his name called until the sixth round, he went on to play 11 years in the NFL and had over 7,800 receiving yards and 21 touchdowns. Not bad for a late-round pick.
3. Pat McAfee
The Colts drafted Pat McAfee in the seventh round of the 2009 NFL Draft out of West Virginia. Punters have to be pretty special to make these kinds of lists and McAfee certainly lived up to the hype. He punted in the NFL for eight years, all of which were spent in Indianapolis. During his eight-year NFL career, McAfee was voted to two Pro Bowls and was named All-Pro once.