Indianapolis Colts left tackle Anthony Castonzo considered retirement a year ago, before ultimately signing a two-year deal to keep playing. He battled injuries throughout his 10th NFL season, including an ankle injury that ended it before Week 17.
On Tuesday, Castonzo announced his retirement. A first-round pick (22nd overall) out of Boston College in 2011, he started all 144 games he played in his career at left tackle for the Colts.
The Colts will add about $16 million to their already nice amount of cap space with Castonzo’s retirement. So they’ll be able to address the need for a left tackle in free agency, though Spotrac’s list of current options is hardly formidable. The 21st pick in the draft could be the path to bringing someone in (Texas’ Samuel Cosmi, Alabama’s Alex Leatherwood, Notre Dame’s Liam Eichenburg, etc.).
But could Castonzo’s replacement ultimately come from within?
Stephen Holder of The Athletic added that Castonzo said he and Quenton Nelson have discussed playing left tackle and what it would be like to play it regularly. Holder suggests they were only “hypothetical conversations”, but also that Nelson isn’t opposed to the idea of moving out from left guard.
Should Quenton Nelson be the Colts’ new LT?
The Colts took Nelson sixth overall in the 2018 draft out of Notre Dame, and he has earned three Pro Bowl nods in as many seasons. He has also earned AP First Team All-Pro honors all three seasons. Simply put, he’s one of the best offensive lineman in the NFL.
Pessimists might say moving Nelson to left tackle, a position he played a few snaps at this year when Castonzo left a game early, would weaken two areas. Castonzo’s retirement leaves one spot in need of reinforcement right now.
The top free agent options at guard are Brandon Scherff and Joe Thuney. Money will be no object for the Colts if they want to go after one of them. If Nelson is tabbed to make the transition to left tackle, as it seems to be trending toward at this early stage, there would not be much of a drop-off at left guard with Scherff or Thuney.
The conversation about Nelson moving to left tackle is two-fold rooted for the Colts. Can he make the move capably? It’s easy to say yes to that right off the bat, until proven otherwise. But can they replace him at left guard? That’s a tougher answer. Free agency, the draft or an internal option (who would also be be moving to a new position) are all possible. It’s really a matter or which of the three avenues would yield the best player to replace Nelson. And that, as long as the Colts get Scherff or Thuney, seems to clearly be free agency.