The former 2011 first round pick out of Boston College (and the final first round pick of Hall of Fame general manager Bill Polian’s Indianapolis tenure) started in 144 career games for the Colts through 10 NFL seasons.
While Castonzo never made a Pro Bowl (even though he should’ve in 2019), he was consistently one of the better starting left tackles in all of football:
Anthony Castonzo has announced his retirement from the NFL:
Anthony Castonzo career ranks:
87.5 PFF Grade (15th)
84.6 Pass-Block Grade (17th) pic.twitter.com/iOPuZjbvb8
— PFF (@PFF) January 12, 2021
Castonzo had previously seriously contemplated retirement during the 2020 offseason, but he instead signed a 2-year, $33 million contract extension—looking to continue his playing career in Indianapolis.
However, he underwent season-ending surgery on his right ankle in late December, having also battled rib and knee injuries earlier in the season. Those injuries presumably pushed Castonzo into calling in ‘early retirement’ with a season still left on his current Colts contract.
Without their blindside bookend this season, the Colts offensive line largely struggled (and the passing game stalled) in his absence with a lack of proven offensive tackle depth behind him—until the team signed fellow veteran Jared Veldheer late in the season.
The 32 year old Castonzo has arguably been the Colts most valuable non-quarterback player throughout his entire career, as Indianapolis is collectively just 4-13 in his absence.
He not only played a premium position, but he played it very well—and only missed 16 total starts over 10 seasons. The career Colt was incredibly underrated for Indianapolis.
Even though he’s not a future Hall of Famer, Castonzo had a great Colts career, remains one of the best offensive lineman in team history, and should be a candidate for the franchise’s illustrious Ring of Honor some day.
Meanwhile, the Colts drafting a top offensive tackle prospect in late April becomes an even greater of a priority right now—unless the franchise plans on switching 3x NFL First-Team All-Pro offensive guard Quenton Nelson to left tackle permanently (which seems unlikely).