Although moving on from Adam Vinatieri after the 2005 season wasn't exactly all on the shoulders of the Patriots, their lack of effort to retain him was definitely a mistake.
Since he was drafted in 1996, Vinatieri became one of the most reliable players on the Patriots roster. In the ten seasons he was with the team, he didn't miss a single game, and that consistency became a significant factor in much of the team's success during his tenure.
During that time, the kicker earned two Pro Bowl selections and two first-team All-Pro selections. On top of that, he led the league with the highest field goal percentage two different times in 2002 and 2004.
After placing the franchise tag on Vinatieri for the 2005 season, the Patriots declined to do it again the following season, allowing him to become a free agent. He went on to sign with the Peyton Manning-led Indianapolis Colts and made sure his former team didn't have the time to match the offer.
The legendary kicker went on to play for 14 more years with the Colts, finally retiring in 2019 at age 47 and easily becoming one of the best ever at the position.
Despite seemingly striking gold again during the 2006 draft when selecting Stephen Gostkowski, the consistency and longevity of Vinatieri's career, on top of how impactful he was in helping the Patriots win their first three Super Bowls, is hard to ignore.