The New England Patriots made history at tight end in 2011.
It's resulted in consistent mismatches for opposing defenses, and a rewriting of the record book for tight ends.
Gronkowski's historic accomplishments in 2011 have been well-documented. In the most prolific season ever by a tight end, he set records at the position for touchdown receptions (17) and receiving yards (1,327).
That only continued on Saturday against the Denver Broncos. Gronkowski tied a postseason record with three touchdown catches, becoming the 16th player and second tight end to do that.
With one more touchdown catch, Gronkowski would join Oakland's Dave Casper as the only tight end with more than three touchdown catches in a single postseason. Casper hauled in five touchdowns for the Raiders over two games in 1977. Oddly, his two opponents in those games were Denver and Baltimore (though it was the Colts franchise).
Including the postseason, Gronkowski has 20 touchdown catches this season. That's tied with Mark Clayton's 1984 season for fourth-most ever. Jerry Rice twice had 22 touchdown catches between the regular season and postseason. The record belongs to Randy Moss, who had 24 for the Patriots in 2007.
Of course, Gronkowski isn't the only star tight end on the Patriots. His historic season overshadowed excellent numbers from Hernandez, who finished in the top five among tight ends in receptions, yards and touchdown catches.
Two of the top five tight ends on the same team? Such a combination is completely unprecedented in NFL history. The numbers are stunning.
Gronkowski and Hernandez combined for 169 receptions. According to the Elias Sports Bureau, that broke the record of 163 set by the 1984 San Diego Chargers. No other team has had 150 catches by tight ends in a season.
Even that Chargers team isn't an adequate precedent for New England's duo. They had three tight ends with 40 or more receptions, rather than two splitting the load. No tight end duo has ever even come within 40 catches of Gronkowski and Hernandez.
The yardage numbers are even more stunning. The combined 2,237 receiving yards for Gronkowski and Hernandez are over 300 more than any team has had at tight end in a season. The old record belonged to those 1984 Chargers, who had four tight ends combine for 1,927 yards.
Needless to say, Tom Brady has found a special connection with this young tight end combo. Consider that he has a 134.2 passer rating when targeting one of the two.
But it's not just what happens when he throws to them. Quite simply, Brady is a different quarterback with the two of them on the field.
When both Gronkowski and Hernandez are on the field, Brady had 31 touchdowns and four interceptions. Otherwise, he threw eight touchdowns and eight interceptions.
Of the two, Hernandez is actually the primary target when both are on the field. In those circumstances, he was targeted 104 times for 75 receptions. Gronkowski had 87 targets and 64 receptions when Hernandez was on the field.
The difference, of course, is that Gronkowski saw many more snaps as the lone tight end. Hernandez acts as much more of a wild card in the offense.
As John McTigue noted in the Stats & Info Blog, Hernandez lined up as a wide receiver for 505 snaps compared to just 255 snaps as a tight end on the line. There were even 61 snaps where he lined up at running back.
Of the two, Gronkowski is far more likely to stay in and pass-block. Hernandez was a pass-blocker on just 2.2 percent of the passing plays for which he was on the field. Compare that to 11.5 percent for Gronkowski.
The Ravens defense should provide a stiff test for the Patriots' passing attack, particularly in the red zone. Baltimore opponents score a touchdown on only 38.1 percent of red zone trips, the lowest rate in the NFL. That includes only five touchdown passes on red zone plays, half as many as the next lowest team.
Not many teams can boast a player like Ed Reed, who has eight interceptions in 10 career postseason games. That's one shy of tying the NFL record. Given that Reed took only five defensive snaps off all season, expect him to be a consistent presence around New England's tight ends.
Gronkowski and Hernandez face a unique challenge in the Ravens, who allowed 665 yards to tight ends during the regular season, the second fewest in the NFL.
Tight ends have historically had little success against Baltimore. In fact, the Ravens have only allowed three 100-yard games by a tight end in their 16 years of existence. It's happened just once in their last 231 games.
Consider that Hernandez and Gronkowski have combined for nine 100-yard performances this season.
Jeremy Lundblad is a senior researcher with ESPN Stats & Information. He provides statistical analysis for ESPNBoston.com.