Formerly of the: Denver Broncos.

Osweiler, who signed with the Houston Texans, is a young guy (25 years old) with relatively little tape -- in eight games last year, he completed 61.8 percent of his passes with 10 touchdowns, six picks and a not-off-the-charts passer rating of 86.4. But all things considered, he responded well to his opportunity last season, going 5-2 in his seven starts, including two overtime wins. And he's an athlete. I think he's going to be pretty good. I'm not saying he's going to be a Pro Bowler, but he'll be more than just an average starter. The Broncos' system is set up to succeed without stellar QB play, especially with their great defense, but I don't think they'll return to the Super Bowl or even necessarily the playoffs without Osweiler in 2016.

Formerly of the: Detroit Lions.

Johnson retired after nine years of producing at high levels on mostly poor Lions teams. With Johnson, I think the Lions would have had a chance to compete for the NFC North title in 2016; without him, I think they're around an eight-win team. They just got so many big plays out of Megatron. Yes, in 2014, Golden Tate (1,331 yards) outgained Johnson (1,077), who dealt with a balky ankle, but Johnson still outpaced him in TDs (eight to four) and yards per catch (15.2 to 13.4). Sure, Tate did well in the three-game stretch Johnson missed that season, but it remains to be seen how he'd handle being the focal point of defenses in the long term. I like signee Marvin Jones; I actually wouldn't be surprised to see him become the No. 1 receiver. But the bottom line is, Johnson is a future first-ballot Hall of Famer still capable of putting up serious numbers, and he will be missed.

Formerly of the: Cleveland Browns.

Mack is a solid player, very smart and athletic, who tried to leave Cleveland two years ago and is being paid a lot to snap the ball to Matt Ryan in Atlanta. The impact of a good center isn't always highly visible, but it's an important position. I like second-year pro Cameron Erving, who the Browns drafted in the first round last year, and I think he can come close to replacing Mack, should he be slotted in at center. But anytime you lose a guy with seven years of experience and the ability level of Mack, you're at a disadvantage, especially when you're a struggling franchise like the Browns. The departure of tackle Mitchell Schwartz (who left for the Chiefs) only compounds the loss.

Formerly of the: New York Jets.

Harrison, who signed with the Giants, is an outstanding run stopper; if you're looking for an endorsement of his abilities, just consider that the Jets ranked second against the run in 2015, allowing 83.4 rushing yards per game. He's a much better athlete than he appears to be, and the Jets don't have anyone on the roster who can stop the run like him. He's the kind of guy offenses really have to focus on, the kind of guy who can occupy two blockers and push linemen back on offense. When you have a guy like that, it makes it easier for studs like Muhammad Wilkerson, Leonard Williams and Sheldon Richardson to do their thing.

Formerly of the: Kansas City Chiefs.

Smith, who signed with the Raiders, is the kind of tall, long-armed cornerback everyone's looking for. You could see what kind of improvement the Chiefs made after Smith returned from his three-game suspension last season. I think one of the reasons Defensive Rookie of the Year Marcus Peters -- who tied for the league lead with eight picks and racked up the passes defensed -- had as many defensive opportunities as he did is that people stayed away from Smith. I don't think the Chiefs currently have anyone on their roster who can replicate Smith's impact, and I think we might see Peters' stats dip a bit in 2016, just because opponents will stay away from him and target whoever's playing in Smith's place.

Formerly of the: Miami Dolphins

The New York Giants' defensive makeover -- of which Vernon was a key part -- vaulted that unit from the bottom of the pack to the top 10. It's not often that you can find a 25-year-old pass rusher with a very quick first-step move like Vernon, and I don't think there's any question the Dolphins will miss him. Yes, they signed Mario Williams, and if Williams -- a straight-ahead player who struggled when asked to drop into coverage in Buffalo last season -- can get anywhere near his 2014 form, he'll be good. But I think Williams' best years are behind him, meaning the Dolphins essentially replaced a rising youngster with a descending veteran. In other words, the line was downgraded.

Formerly of the: Oakland Raiders.

The 39-year-old Woodson didn't have to retire because of lost ability, as he was still making significant contributions to the Raiders (five picks, nine passes defensed, 74 tackles) in his 18th NFL season. He was simply a great leader, someone to whom the younger players flocked, and he helped make his teammates better pros. His biggest plus as a player was getting everyone lined up correctly, and as a result, you didn't see as many missed coverages and cheap touchdowns scored against Oakland as you might have otherwise. Yes, the secondary added Smith, who is a definite upgrade at corner, but in losing Woodson at safety, the unit lost the guy who held the whole game plan together, so to speak. He was a special, special player, a first-ballot Hall of Famer -- the bottom line is, there just aren't many players like him around.

Formerly of the: Denver Broncos.

Trevathan, who signed with the Chicago Bears, is a balanced linebacker, good at defending both the run and the pass, a leader who can contribute on all three downs. Defensive lineman Malik Jackson, who left for the Jaguars, had a great 2015 and will definitely be missed, but I think Denver might miss Trevathan more, thanks to a comparative lack of depth at the inside linebacker position. I think the Broncos think Todd Davis can replace Trevathan, but I don't feel that way. Trevathan is a playmaker whose speed and recognition will be tough to replace.

Formerly of the: Los Angeles Rams.

Laurinaitis, who was cut by the Rams in February, is a tremendous leader who sets the tone with his work habits. He's a three-down player who makes a lot of tackles. The Rams apparently want to replace him in the middle with Alec Ogletree, and the youngster might be faster, but I don't know if he has the same recognition skills as Laurinaitis, who has a great understanding of the game and how to play it. Wherever he signs, Laurinaitis is going to help a team.

Formerly of the: Chicago Bears.

Forte, who is headed to the Jets, slowed down in his eighth season, and his production dipped, but he's still a very good receiver who caught 102 passes two years ago. He also knows how to run the ball. Chicago's presumptive replacement, second-year pro Jeremy Langford, is a straight-ahead guy who is on the way up, but I don't think he's ready to play at Forte's level in 2016, at least not in the passing game.