Each off-season, fans gets excited about the opportunity for their teams to restock and retool talent at positions of need. For as long as most Colts fans can remember, one of those positions is defensive tackle. As a result, when the draft and free agency opportunities come and go, fans clamor for their favorite players and hope that tremendous improvement will be made in whichever area they identify as needing the biggest upgrade.

Over the last four off-seasons, the Colts have added four defensive tackles via the draft, one undrafted free agent, and have three players on the roster signed from waivers or free agency. This means no defensive tackle on the team has more than three full years of experience with the Colts, which partially explains the reason fans will continue to clamor for more options — none of the defensive tackles on the team have really proved themselves to be stalwarts on the defensive line.

How should fans change their lens in reviewing and evaluating the play of defensive tackles entering the league or spending their first seasons with the Colts? What should they really expect?

Nate Dunlevy at 18to88.com follows the draft each year with a breakdown of realistic expectations for each player the Colts select. There is a lot a fan can learn from reading his evaluations and projections, so Coltzilla would encourage our readers to take a look at his stories.

Coltzilla reader Fred Scheppele brought another story to our attention. Len Pasquarelli of CBSSports.com discussed young defensive tackles. He breaks down the top rated defensive tackle prospects of the 2009 NFL Draft and examines what success each player had in their first and second years. While this is a look at one year only, the story illustrates a better idea of what Colts fans should expect from rookie defensive tackles, second-year defensive tackles, and those who have recently joined the team.

Former 9th pick overall, B.J. Raji started only one game of his rookie season for the Green Bay Packers and registered 25 tackles and one sack in 16 appearances. In his second season he became a force to be reckoned with, recording 39 tackles and 6 1/2 sacks, which helped the Packers defense improve — and helped Green Bay earn a Super Bowl victory. Without doubt, Raji would be considered an early NFL success story.

With this backdrop Pasquarelli notes:

Most league observers agree that a player, regardless of his position, generally makes the biggest advancement of his career in his second season. That seems especially true on the defensive front, where first-year players often struggle, no matter the draft pedigree, and where the gestation period can be a painful one.

This is an interesting and telling observation that strikes at the core of arguments that first round players, regardless of position, are expected to be meaningful contributors as rookies. There is no doubt that the biggest slam dunks in the league are players like Raji who was a sixteen game contributor, or rookie superstars like Ndamukong Suh who had 10 sacks as a rookie (second overall 2010). Just one spot after Suh was Gerald McCoy, who played in thirteen games for Tampa Bay and managed 22 tackles and 3 sacks — a solid performance but not nearly the caliber of the players discussed before him.

As for other players, Pasquarelli notes that Ziggy Hood and Matt Shaughnessy took big steps in their second years. Robert Ayers, Peria Jerry, Aaron Maybin, Jarron Gilbert, Everette Brown, and Ron Brace did not. The list of players failing to take big steps is rather distinguished — these players were highly sought after, discussed, and all projected to be potential difference makers. In their first two seasons, they have not lived up to the hype.

This does not mean that none of these players will manage to have successful NFL careers. What it means is that expectations that rookie and second-year defensive linemen will be “all world” right out of the gates is unrealistic. Unless a team was lucky enough to draft a player named Raji or Suh in the last two NFL drafts, a little patience for development and blossoming was and continues to be a necessity.

Here is a look at the statistics put up by some of the players listed above:

Peria Jerry – 24th overall
2010: 16 games, 0 starts, 9 tackles, 2 sacks, 1 PD
2009: 2 games, 2 starts, 1 tackle

Ziggy Hood – 32nd overall
2010: 16 games, 9 starts, 20 tackles, 3 sacks, 1 PD
2009: 16 games, 0 starts, 8 tackles, 1 sack, 2 PD

Ron Brace – 40th overall
2010: 13 games, 5 starts, 23 tackles
2009: 9 games, 2 starts, 8 tackles

Fili Moala – 56th overall
2010: 16 games, 16 starts, 26 tackles, 1 PD
2009: 10 games, 1 start, 7 tackles

Jarron Gilbert – 68th overall
2010: 1 game, 0 starts, 1 tackle
2009: 4 games, 0 starts, 1 tackle

By comparison, Indy’s own Fili Moala outperforms all of the players drafted in his range except Ziggy Hood. While Peria Jerry has picked up a couple of sacks, he has not been nearly as big of a steady factor or contributor as Moala. Also, as has been mentioned before at Coltzilla, while Moala did not record any sacks in 2010, he was markedly more effective penetrating the pocket and generating pressure on opposing quarterbacks. There was more than one sack that I give Moala credit for creating in 2010.

In the end, Moala has not proven to be a game-changing mind-blowing defensive performer in his first two seasons. Of course, Pasquarelli’s story explains that this is to be expected. Even players who makes jumps in their second season, like Moala, are not often Pro Bowl performers this early in their careers.

These observations should temper Colts fans’ expectations for Drake Nevis in his rookie season. While he certainly is the kind of disruptive interior defensive player Indianapolis covets, he will most likely not start a single game as a rookie and a single sack and double digit tackles would be exceptional for his draft position.

Everyone wants improvement and change to happen immediately. In reality, particularly on the defensive line, it takes considerable time for improvements to occur.