Led by an unexpected quarterback battle and a series of roster changes, the Indianapolis Colts' depth chart has become one of the most interesting in the league entering the 2025 season. While many are focused on the Anthony Richardson-Daniel Jones saga, the Colts' biggest initial surprise comes on the defensive end, where they currently list Cameron McGrone as a starting linebacker.
Quarterback is easily the most important position in the sport, making that battle an easy headline of the team's offseason. However, even if Richardson maintains the job, the Colts are on track to retain just 15 of their 22 offensive and defensive starters from a year ago. Indianapolis does not want any part of its 8-9 season to carry over into 2025, but the lack of retention will be a key factor to monitor early in the season.
Most of the team's roster turnover comes defensively, where Indianapolis retained just seven of its 11 starters from 2024. Of them, only six are currently listed as starters on the Colts' 2025 initial depth chart. Indianapolis supplemented the losses with multiple key signings, but it will still debut a new-look unit led by first-year defensive coordinator Lou Anarumo.
The Colts' linebacker corps will be arguably their most interesting situation to monitor. While returning leading tackler Zaire Franklin, Indianapolis lost starters E.J. Speed and Grant Stuard in free agency. They did not make any noteworthy additions to the group, leaving multiple starting jobs up for grabs.
As they prepare to enter the preseason, McGrone has shockingly emerged as the favorite to win one of those vacancies. Whether or not that is still the case by Week 1 remains to be seen, but there is no bigger surprise on the Colts' unofficial 2025 depth chart release.
Cameron McGrone is biggest surprise of Colts' initial depth chart

With Speed and Stuard out of the picture, the Colts were forced to address their linebacker void internally. Many believed that Jaylon Carlies, who recorded 36 tackles as a rookie in 2024, would be the favorite, but Indianapolis appears to be favoring Cameron McGrone.
A former fifth-round pick of the New England Patriots, McGrone is easily one of the most experienced linebackers on the team. However, most of that experience has been accrued on special teams. After spending his rookie season on the Patriots' practice squad, McGrone has appeared in 22 games for the Colts over the last three seasons with zero starts at linebacker.
To this point, McGrone has established himself as a special teamer, and a mediocre one at that. He played just one defensive snap in 2024, as opposed to 156 on special teams. McGrone ended the year with just six total tackles, all either on kickoffs or punt returns.
Although McGrone did not enter the league as a highly touted prospect, many initially hoped that he would develop into a future starter. He entered the draft after a standout career at Michigan and has the type of infectious energy that his teammates seem inclined to follow. Yet, given how his first few seasons have turned out, it is surprising that this is the path McGrone has taken to become a starter.
As an Indianapolis native, McGrone has the support of the fan base. He has not generated much hype in training camp, but has evidently done enough to prove himself as the second-best linebacker on the roster in Anarumo's eyes. The job is not done, but McGrone has put himself in a position to receive the biggest opportunity of his professional career.
Cameron McGrone will need to prove himself in preseason

McGrone might be listed as the starter entering the preseason, but he will have to hold onto that job throughout. He played one series in the Colts' opening preseason game against the Baltimore Ravens, recording two tackles.
Carlies is the main threat to McGrone's position, but veterans Segun Olubi and Joe Bachie will also play a factor. Olubi, a former undrafted free agent, has been higher than him on the depth chart over the past two seasons. The 25-year-old had a strong showing against the Ravens, recording five tackles.
Bachie, 27, could be the biggest wild card of the group. He has just two career starts under his belt, but followed Anarumo to the Colts in free agency. Bachie has spent the last four years with the Cincinnati Bengals, where he was a key rotational defender in Anarumo's system.
With three preseason games remaining, the job surprisingly seems to be McGrone's to lose. It would not be surprising to see either one of Carlies, Bachie or Olubi in the starting lineup by Week 1, but they would have to put together a stellar end to the offseason to make that happen.
The results of McGrone in the starting lineup will speak for themselves, but after entering the offseason looking to compete for a roster spot, he has easily had one of the best offseasons on the team. Regardless, seeing McGrone at the top of the Colts' unofficial 2025 opening depth chart release was easily the biggest surprise.