Well, I knew it was coming. I just wish it had happened between the final Sunday of the NFL’s regular season and the first wild-card weekend playoff game when I recommended an ‘over/under’ of head coaches fired prop at Bovada for that stretch.

I am speaking of the retooling Indianapolis Colts firing Head Coach Jim Caldwell, which happened Tuesday. You knew he was a for sure goner when owner Jim Irsay pretty much fired everyone in the front office right after the season ended. No new GM – in this case Ryan Grigson – wants to be left with the old regime’s head coach (the Chicago Bears are breaking that rule).

A good column on SI.com points out that Caldwell’s demise really started with the Super Bowl loss to New Orleans two seasons ago. Indianapolis took a 16-2 record into that Super Bowl in Miami in early February 2010 and were solid favorites over the Saints but lost. Since then, the Colts are 12-21. Sure, they snuck into the playoffs last season at 10-6 in winning a weak AFC South but were punked at home by the Jets. And this season Indy was an abject disaster once Peyton Manning had neck surgery, finishing at 2-14 but at least earning the No. 1 pick in April’s draft and the chance to take Manning’s successor, Stanford’s Andrew Luck.

It’s hard to totally blame Caldwell, who finished with an overall mark of 28-24, including 2-2 in the playoffs, for the train wreck that was this season, but it seemed like the Colts quit from Day 1. I bet Caldwell lands a college head coaching job next season.

Bovada has released a prop on Caldwell’s replacement, and one thing many “experts” seem to agree on is that it will/should be an offensive-minded guy to help groom Luck – whether Manning is a Colt next season is a story (and likely a prop) for another day. With an apparent franchise quarterback on the way, this would seem to be a coveted job opening. But the biggest names won’t be coming since they won’t have personnel authority (i.e. Jeff Fisher, who reportedly was contacted by Indy but turned the Colts down before taking the Rams job).

Grigson wants a coach in place before the Super Bowl, which is, of course, in Indy this season. Here are the Bovada betting candidates and my take on each:

Marty Mornhinweg, Eagles offensive coordinator (5/2): Why is a guy who was 5-27 in his two years as head coach of the Detroit Lions the leading candidate? Well, most blame that Lions mess on former GM Matt Millen. Mornhinweg has been with the Philadelphia since 2003, and he's been the offensive coordinator since 2006. He is credited with reviving Michael Vick’s career. And Grigson is a former Eagles’ personnel guy so he obviously knows Mornhinweg well.

Greg Roman, 49ers offensive coordinator (4/1): He seems to have worked wonders with San Francisco quarterback Alex Smith and was a reported finalist for the Penn State head coaching gig.

Brad Childress, former Vikings head coach (5/1): Obviously things didn’t end well in Minnesota, with Childress hitching his wagon a season ago to Brett Favre. But Childress is considered a QB-friendly coach and was 39-35 in five years with Minnesota (including 10- and 12-win seasons in 2008 and 2009), and the Vikings were one Favre interception away from the Super Bowl in 2009 (which would have been against these Colts).

Dennis Allen, Broncos defensive coordinator (13/2): That Patriots playoff blowout loss aside, the Broncos did have one of the NFL’s better defenses this year (although it faded at the end of the regular season). Allen was the Saints’ secondary coach when they beat the Colts in Super Bowl XLIV.

Mike Zimmer, Bengals defensive coordinator (13/2): Cincy had a very good defense this season and last. Zimmer was in the mix for the Dolphins’ head coaching job but didn’t get that and apparently will interview for the Bucs’ opening as well.

Marc Trestman, head coach of CFL’s Montreal Alouettes (7/1): The Alouettes are a powerhouse up north and the offensive-minded Trestman has been an NFL assistant, including offensive coordinator, for several teams. He was up for the University of Miami head coaching gig before it went to Al Golden.

Perry Fewell, Giants defensive coordinator (15/2): He had a 3-4 record with Buffalo on an interim basis to close out the 2009 season. And he’s a hot name right now with the G-Men surging. But, obviously, it would be tough to hire him before the Super Bowl if the Giants are playing in it. Think that might be a distraction with the game in Indy?

Tony Dungy, former Colts head coach (15/2): This is just on the list for shock value. Dungy still gets calls about jobs, but he’s happy with his life, including mentoring players, and won’t be coaching again.

Bill Cowher, former Steelers head coach (10/1): No chance here. First off, Cowher would cost a ton. And second, he would want a say over personnel. I am surprised he hasn’t landed somewhere yet this year – maybe he really is done coaching.

Kirk Ferentz, Iowa head coach (12/1): He seems to always be mentioned for NFL jobs, but what has Iowa done the past few years? Plus Ferentz always says he’s happy where he is.

Jon Gruden, former Bucs head coach (15/1): Wouldn’t it be ironic if Gruden followed Dungy in Indy – one coach removed – like he did in Tampa Bay? Chucky did just sign a long extension to stay on “Monday Night Football” and he could have had better jobs than this if he wanted them.

Most reports around the Colts expect a young, charismatic coach to be the choice because Grigson is young and it would be the opposite of Caldwell and Dungy. A next-generation guy: someone like the 49ers’ Jim Harbaugh, who probably would be candidate No. 1 if he was still at Stanford considering he is a former Colts quarterback and is still loved in Indianapolis. It probably won’t be a college head coach, however, because those haven’t worked out well in the NFL recently other than Harbaugh.

I’m not sold it will be any of these guys, but I would say the best value on the board for my predictions is Trestman at 7/1. Trestman has been a success in the pros, both as an NFL offensive coordinator and QBs coach and having won two Grey Cups with Montreal. Plus he spends his off-season mentoring young quarterbacks coming out of college so he would be a perfect fit for Luck. Trestman has one year left on his deal with Montreal, so any potential discussions between he and the Colts would first require the Als’ permission, but that’s just a formality.