Here’s what we know about Ndamukong Suh and the Lions as free agency approaches. It opens at 4 p.m. on Tuesday, although Suh’s agent Jimmy Sexton can start talking to other teams on Saturday.

1. There’s still a chance that Suh will be back in Detroit. The Lions want him and know they will have to pay. ESPN analyst Louis Riddick thinks  he will get a record deal with way more than $50 million in guarantees. Suh to Miami is the hot rumor today. Will it get done with the Lions?  No one knows, but there is still a chance.]

PHOTOS: Ndamukong Suh's 2014 season

2. If Suh does not return, all is not doom and gloom. He is not replaceable one-on-one, but the Lions can find solid replacements, coach them up and tweak the defense a bit. It was the second-best defense in the NFL last season and defensive coordinator Teryl Austin is known for getting the most out of his players. Defensive line coaches Kris Kocurek and Jim Washburn are the among the best in the business.

3. Don’t expect GM Martin Mayhew and team president Tom Lewand to get fired if Suh goes to another team. Not sure why so many fans want that to happen.  It seems people forget the Lions were 11-5 last season and went to the playoffs. Mayhew and Lewand are doing the best they can after having to deal with huge salaries of Calvin Johnson (second overall pick in 2007), Matthew Stafford (first overall pick in 2009) and Suh (second overall pick in 2010). The Lions didn’t have many options with the three big rookie contracts. That changed with the new Collective Bargaining Agreement in 2011 which limits rookie contracts, but it was too late for the Lions.

4. Also remember it takes two sides to negotiate. The Lions started the process over a year ago. Since I’m not at the negotiating table, not sure who was at fault for dragging their feet and not getting a deal done before 2014 season. Possibly blame can be assessed on both sides.

5. Suh has all the leverage. It might be different if the Lions had picked up the fifth-year option on Nick Fairley, but they did not. Fairley (who started eight games in 2014) and C.J. Mosley (who also started eight games) can also become free agents. Suh is one of four Lions’ defensive tackles from 2014 who can become a free agent on Tuesday. Fairley seemed to get his act together in 2014 by losing weight, better conditioning and an improved work ethic. He was out the second half of the season with a knee injury. He can be very good, but we haven’t seen it consistently.

(Follow @PaulaPasche on Twitter. Order her book,  “100 Things Lions Fans Should Know & Do Before They Die’’ here. It’s also available at bookstores.)