5) Ndamukong Suh, DT, Detroit Lions, 2010
Regular-season stats: 66 tackles, 10 sacks, one interception, one forced fumble, 16 games played (16 starts).
Suh -- named first-team All-Pro as a rookie -- certainly was impactful right out of the gate. Detroit had won all of two games over the two seasons before the menacing tackle from Nebraska showed up; with Suh in the fold, the Lions' defense was no longer a pushover, and Detroit improved to six wins in 2010. Suh held his own against some of the better guards in the league that season -- in addition to his ability to bring down quarterbacks, you just can't look past that tackle total. That's a solid figure for an interior defender who, by the second half of the season, was consistently facing double teams. Oh yeah, and judging by the contract he just got from the Miami Dolphins, this guy is still pretty good.
4) Jevon Kearse, DE, Tennessee Titans, 1999
Regular-season stats: 14.5 sacks, eight forced fumbles, 16 games played (16 starts).
"The Freak," as he came to be known, was all over quarterbacks in his rookie season -- and the impact of his freshman year went beyond that. The new-look Tennessee Titans, finally playing in front of home crowds in Nashville after spending two years in two different Tennessee stadiums following their move from Houston for the 1997 season, made it all the way to Super Bowl XXXIV. And they couldn't have done it without Kearse, who set an NFL rookie record for sacks (at least, since the stat became official in 1982) while continually making the Tennessee secondary look better than it really was. Kearse was named first-team All-Pro and added three more sacks in the postseason. Unfortunately, he was never able to match his rookie-year production over the rest of his 11-year career.
3) Reggie White, DE, Philadelphia Eagles, 1985
Regular-season stats: 13 sacks, 13 games played (12 starts).
White was fantastic that season for ill-fated Eagles head coach Marion Campbell. Yet, unlike others on this list, White was not named first-team All-Pro as a rookie. In fact, he didn't even make the Pro Bowl. Two factors worked against him in terms of getting more acclaim: 1) USFL refugees like White didn't receive much respect in '85; it wasn't until Herschel Walker and Jim Kelly joined the NFL in 1986 -- and the rival league folded -- that people started taking notice of players like White. 2) The 1985 season might have been the best year ever for defensive ends in the NFC. Seriously. Richard Dent and Dan Hampton were in Chicago, tearing it up for the best defensive team in history, while the Redskins' Dexter Manley and Charles Mann combined for 29.5 sacks, and Dallas' Ed "Too Tall" Jones and Jim Jeffcoat in Dallas totaled 25 between them. So White, who toiled for two seasons with the Memphis Showboats before joining Philly, was barely noticed despite averaging a sack per game (!) for a cruddy Eagles team. He was dominant almost from Day 1.
2) Al "Bubba" Baker, DE, Detroit Lions, 1978
Regular-season stats: 23 sacks, 16 games played (16 starts).
Baker's stat line tells you all you need to know. You kidding me? How does a rookie total 23 sacks in 16 games? Not only that, pass-blocking rules were liberalized during the offseason prior, meaning offensive tackles could use techniques they never used before. Yet somehow, the AP Defensive Rookie of the Year blew right by 'em, to the tune of a sack and a half per game. In fact, the Lions' pass rush became so feared with Baker that it earned the nickname the "Silver Rush." He was the ultimate speed rusher, as he played at a relatively slim 6-foot-6 and 250 pounds his first couple of years. In five seasons as a Lion -- only 67 games -- Baker recorded an incredible 75.5 sacks. Most of those were unofficial, of course, but it should be noted that Baker posted 8.5 sacks in nine games during the strike-shortened 1982 season, the first season sacks were deemed an official statistic. My colleague @MarcSessler could tell you how good Baker was in his mid-30s for the Cleveland Browns, but that's an article for a different day.
1) "Mean" Joe Greene, DT, Pittsburgh Steelers, 1969
Regular-season stats: 14 games played (14 starts).
We're not going to give you a bunch of stats to support "Mean" Joe Greene's candidacy for the top spot on this list -- not that there are a ton of official stats available for defensive linemen going back to '69 anyway. The guy changed a whole culture of losing in Pittsburgh. Here's all you need to know: In his first season in Pittsburgh, the Steelers went 1-13, and yet Greene was named first-team All-Pro, despite playing at a time with Hall of Famers -- first-ballot Hall of Famers, mind you -- Bob Lilly, Merlin Olsen and Alan Page dominating at defensive tackle. And it's not like Greene had college fame to boost his popularity with the voters who selected the all-star team; he went to North Texas State, after all. The Mean Green! Few had heard of the rather small football school in Denton, Texas, which is now called North Texas University. (Your friendly writer is a Mean Green alum, but hey ...) Point is, for Greene to go from being a relative unknown when drafted to someone who was recognized as one of the two or three dominant players at his position in a matter of months was incredible.
Pre-Super Bowl era: Gems hidden by patchy stats
Finding defensive linemen who dominated as rookies prior to 1966 ain't the easiest chore. For one, tackles and sacks were recorded by teams, and neither stat was official until the 1980s. Even then, there's some debate about how different teams recorded tackles. Moreover, prior to the mid-1950s, most of these guys played both ways; thus, trying to discern whether a guy stood out on defense independent of his offensive performance is darn near impossible without access to additional source material.
Luckily, I have access to said source material. An easy player to mention is former San Francisco 49ers great Leo Nomellini, who entered the NFL in 1950, right when football as played in the league was transforming into a more modern game of specialization. Nomellini was an impact player from Day 1, making the Pro Bowl in his first year. Considering his debut season was the 49ers' first in the NFL, reputation couldn't have played that much of a role -- he was just that good. Ditto for Merlin Olsen, an awesome interior force who used brains as often as he did brawn, from his first year with the Rams in 1962 until the day he hung 'em up in 1976 -- a year which marked the first time he missed the Pro Bowl in his career.
Lastly, Bruiser Kinard, he of the ill-fated Brooklyn Dodgers and, later, New York Yankees (yes, those were NFL teams once upon a time), made his presence known early. Despite playing at a scant 195 pounds, Kinard was known as an outstanding tackler -- and those were at a premium in the days of 10 passes per game. Kinard and Byron "Whizzer" White were the only rookies to earn All-NFL honors in 1938.