The Panthers' decision to fire Ron Rivera on Tuesday was such a surprise that even Rivera was caught off guard by the news. Although Rivera was on the hot seat and knew he might eventually be let go at the end of the year, the Panthers coach didn't seem to think there was any chance he would be canned during the season.

So why did Panthers owner David Tepper decide to fire Rivera with just four games left to play? Why not let him coach out the season and then fire him after Week 17?

Tepper was asked those exact questions on Tuesday and he didn't try to duck them. During an interview with the Panthers official website and a later interview with local media, Tepper gave a thorough explanation for why he decided to let Rivera go with just four weeks left in the 2019 season. 

"I'm not going to start a search and not tell Ron Rivera I'm starting a search," Tepper told reporters. "I'm not going to disrespect him."

The owner's decision basically boiled down to two things: He wanted to start interviewing candidates now and he didn't want to be interviewing those people behind Rivera's back (check out CBS Sports Senior Writer Jonathan Jones' take on the Panthers' plan here). 

"Quite frankly, our season is not over, but as far as making the playoffs [it is]," Tepper told the team's website. "I could make the change now. I could make it later. There are competitive reasons why I wanted to make sure that we were out there looking at all personnel possible for the future. I don't want to in any way, shape or form didn't want to be having inquiries where Ron didn't know what I was doing. I don't want to be doing things not up front. It's just not who I am, so I'd rather be straight up and honest."

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If Rivera had stayed on to coach through the end of the year, Tepper would likely have had to reach out to coaching candidates through backchannels, which isn't something he really wanted to do. 

"If I'm going to make a change, I'm going to take a change," Tepper said. "Not to get a competitive disadvantage over other teams, if I need to talk to people, I want to talk to them and I want to talk to them in a straightforward, honest way."

After revamping the business side of the organization following his purchase of the team in May 2018, Tepper felt it was time to now revamp the football side of things. 

"I came here two years ago. I wanted to show patience on the football side to see how it was going," Tepper said. "On the business side, we made vast and sweeping changes, and I didn't want to make those vast and sweeping changes on the football side. I wanted to take time and patience to see what could go, and how it could go. I just thought it was time -- given the way things have gone the last two seasons -- to put my stamp on this organization on the football side, as we've done on the business side of the organization. As much respect as I have for Ron, I think a change was appropriate to build things the way I want things to be built."

With Rivera now out, it seems that Tepper's plan is to now replace him with a offensive-minded coach who embraces analytics. To check out a list of six candidates the Panthers might consider for the job, including Patriots offensive coordinator Josh McDaniels, be sure to click here.