The Detroit Lions were one of the top stories in the NFL last season. Many expected the Lions to contend for the NFC North title because they finished the previous season on a hot streak, but the team's history was one of failure in nearly all situations.

While the team appeared to have plenty of talent, there was every reason to believe that if anything could go wrong for the Lions, it would. This was a team that had not won a division title since 1991, and the consistent heartbreak in the Motor City over the fortunes of the football team seemed to be never ending.

But head coach Dan Campbell was not about to let history get in the way of a powerful roster that included Jared Goff at quarterback, Amon-Ra St. Brown at wide receiver, Aidan Hutchinson as a game-changing edge rusher and linebacker Alex Anzalone as a tackling machine.

The Lions started the season by defeating the defending Super Bowl champion Kansas City Chiefs on the road, and they rode that impressive start to an excellent season. The Lions won the NFC North title with relative ease, and they played with a determination that has not been seen from the franchise since the start of the Super Bowl era.

Shocking postseason success for the Lions

Not only did the Lions earn a spot in the playoffs, they won a pair of postseason games against the Los Angeles Rams and the Tampa Bay Buccaneers. They played for the NFC Championship and had the San Francisco 49ers on the ropes for a large portion of the game before they fell in heartbreaking fashion by a 34-31 margin.

Experience and one lucky break were probably the biggest reasons the Lions fell short of getting to the Super Bowl for the first time in team history.

It's clear the team is on the right path, but these are the Lions. What appears to be a winning road could take a bad turn at any time.

As a result, general manager Brad Holmes and Campbell must look at the roster carefully and continue to make moves that will help the team improve.

As strong as the Lions were in finishing with a 12-5 record in the regular season, this is not a team without vulnerabilities.

The biggest area seems to be on the defensive side of the ball. The Lions ranked 19th in yards allowed, giving up 336.1 yards per game. They also ranked 23rd in points allowed, giving up 23.2 points per game.

The Lions will almost certainly profess to bring in the top players in the NFL Draft, regardless of position. That's how nearly every team explains their offseason philosophy.

However, the Lions need to get better on defense, and adding top defensive players in the middle and late rounds of the draft has to be part of Holmes' thought process.

Edge rusher Brandon Dorlus should improve the Detroit pass rush

The Lions have been dependent on Hutchinson when it comes to rushing the passer. He had 11.5 sacks last year along with 14 tackles for loss, 3 forced fumbles and 2 fumbles recovered. Outside of Hutchinson, linebacker Alim McNeil was second on the Lions with 5.0 sacks.

Oregon's Brandon Dorlus could be a middle-round draft choice who could help the Lions improve their pass rush. He is able to line up at multiple spots on the defensive line and put pressure on the quarterback. His best position in the NFL could be as an edge rusher, and that would allow him to use his 6-3, 285-pound frame to his best advantage.

He had 5.0 sacks last season along with 6.5 tackles for loss and 9 passes that he was able to bat down. That last stat shows an awareness that he knows how to make key contributions even when he can't get to the quarterback.

CB Cam Hart has the tools to upgrade the Lions  secondary

Cam Hart has the kind of size that could benefit the Lions next season. He is nearly 6-3 and 207 pounds, and he is clearly a big hitter for the position. That's something of a bonus, because he is also quite skilled in coverage.

Hart presses hard and can stay in the hip pocket of dynamic receivers. He does not react to fakes from either the quarterback or the receiver, and he can stay with double moves better than many cover men. One of the reasons for that is his excellent speed. He plays with a confidence, knowing that receivers are not going to burn him when they reach top gear.

On the negative side, he has had three shoulder surgeries in the past and he doesn't always find the ball right away. However, he looks like a player who could help the Lions in the long run.