Posted by Chase Stuart on June 11, 2008
On Monday and Tuesday, I looked at some of the best seasons by returners in league history. As noted yesterday, Josh Cribbs' 2007 season was truly remarkable. He added 486 more adjusted yards than the league average kickoff returner would have produced, and another 136 adjusted yards above what the league average punt returner would have compiled with the same number of returns. Those 622 adjusted yards over average was the single highest total by any one player since the merger.
year KR VAL PR VAL RET VAL Josh Cribbs 2007 486 136 622 Michael Lewis 2002 297 211 508 Dante Hall 2003 266 211 477 Mike Nelms 1981 347 123 470 Brian Mitchell 1994 242 181 423 Mel J. Gray 1991 247 175 422 Billy Johnson 1977 118 283 401 Mel J. Gray 1994 347 42 389 Billy Johnson 1975 76 312 388 MarTay Jenkins 2000 392 - 9 383 Terrence McGee 2005 373 0 373 Derrick Mason 2000 208 158 366 Tyrone Hughes 1993 178 182 360 Ron J. Brown 1985 359 0 359 Eddie Brown 1976 108 249 357 Brian Mitchell 2002 222 134 356 Eddie Drummond 2004 220 129 348 Raymond Clayborn 1977 340 0 340 Ron Smith 1973 155 173 328 Jerome Mathis 2005 356 - 30 325 Jerry Azumah 2003 325 0 325 Glyn Milburn 1995 260 61 321 Brian Mitchell 1995 227 89 316 Cecil Turner 1970 322 - 9 314 Tim Brown 1988 288 25 313
When comparing returners to returners, using adjusted yards (adjusted meaning simply giving an additional ten yards for every TD score) compared to league average works well as a measure of accomplishment and value. But what if we want to compare returners to QBs? Well, that's a little more complicated.
For example, here's a list of the top ten QBs in yards over average last year, using adjusted yards per attempt compared to the league average.
1560 Tom Brady 703 Peyton Manning 669 Tony Romo 650 David Garrard 626 Brett Favre 612 Ben Roethlisberger 474 Jeff Garcia 428 Donovan McNabb 413 Matt Hasselbeck 331 Jay Cutler
Guys like Derek Anderson, Drew Brees and Carson Palmer don't even make this list. And while I think this does a nice job of measuring the value added by each QB intraposition, it doesn't do a good job of showing the relative value of Brett Favre compared to Josh Cribbs. It doesn't do a good job for lots of reasons, but the simplest reason is because it basically says they were equally valuable last year.
The flaw in the math is that an average QB is actually pretty valuable. An average kickoff returner isn't really valuable at all. Why? Well, anyone can find a KR that can come close to the league average; there aren't league average QBs just hanging around.
So how do we compare the two? The league average adjusted yards per pass ratio last year for quarterbacks was 5.86. More importantly, 85% of the passes thrown last year were by QBs who averaged at least 4.75 AY/A. I feel pretty comfortable using that as a replacement level number. That's in between what Vince Young and Matt Moore averaged. I may be wrong, but I think almost every team can find a QB to average at least 4.75 AY/A, so if you're not averaging that, you really have almost no value. Only four teams had their QBs average under that -- Oakland, Carolina, St. Louis and San Francisco. In other words, I feel pretty comfortable with Miami's team QBs (4.89 AY/A) getting negligible value in this system.
Conversely, 85% of all kickoff returns last year were by kickoff returners who averaged at least 20.00 AY/KR, which is only 2.77 adjusted yards below league average. Additionally, about 85% of all punt returns were by players who averaged at least 6.15 adjusted yards per punt return, which was 3.14 adjusted yards below average.
What's that all mean? If you take 20.00 AY/KR and 6.15 AY/PR to be "replacement level", that means Josh Cribbs added 649 adjusted kickoff return yards above replacement and 231 adjusted punt return yards above replacement. So he brought in about 880 return yards above replacement level last year.
How does that compare to say, the adjusted yards over replacement level added by the top QBs?
2067 Tom Brady 1155 Peyton Manning 1126 Tony Romo 1095 Brett Favre 967 Ben Roethlisberger 906 Matt Hasselbeck 935 David Garrard 843 Donovan McNabb 741 Jay Cutler 761 Jeff Garcia 645 Drew Brees 675 Kurt Warner 627 Carson Palmer 597 Derek Anderson 553 Jon Kitna
Cribbs ranks ahead of all but seven QBs. Is it actually possible that Cribbs was more valuable to the Browns than Derek Anderson? My gut reaction, along with my second, third and fourth thoughts, tell me the answer is 'no'. But consider this -- our guts would also tell us that say, Brodie Croyle and Josh Cribbs would be way worse than Derek Anderson and a mediocre punt and kickoff returner, right?
Well, maybe not. Derek Anderson had 529 pass attempts last year, and totaled 3,787 yards, 29 TD and 19 INT. That's an average of 6.11 AY/A, or 3,222 adjusted yards. If we give our mediocre kickoff returner (let's call him Dominic Rhodes) 59 KO returns, we'd expect 1,180 adjusted yards. If we give our mediocre punt returner (let's call him Adam Jennings) 30 punt returns, we'd expect 186 adjusted yards. Therefore, our KR, PR and QB will give us 4,588 yards.
Now, let's look at Brodie Croyle and Josh Cribbs. We know Cribbs gave us 1829 adjusted yards on kickoff returns, and 415 adjusted yards on punt returns. If we give Brodie Croyle 529 pass attempts -- that's what Derek Anderson had last year -- then Croyle would end up with roughly 2,898 passing yards, 14.2 TDs and 14.2 INTs. Those numbers, of course, aren't very good. That's only 2,401 adjusted yards.
But Cribbs (the KR), Cribbs (the PR) and Croyle give us 4,759 adjusted yards on the season. And that's almost 200 more yards than Derek Anderson, Dom Rhodes and Adam Jennings gave us. Looking at it in that light, I can sort of begin to see how Cribbs was better, or more precisely, more valuable to the Browns than Derek Anderson. And that's not really a slight on Anderson -- Cribbs was more valuable than Donovan McNabb, Jay Cutler, Jeff Garcia and Drew Brees, too.
As mind boggling as that might seem, keep two things in mind. One, don't use Cribbs as a proxy for "the best kick returner in the league." Because this wouldn't be true, well, ever. Cribbs had by far, the single greatest season by a returner since the merger. So you might want to throw what you normally think of great returners out the window. Two, we should understand that Cribbs' season was an anomaly, and he had some luck, and he's obviously not "that" good. But it did happen and he was valuable. Tom Brady's not going to throw for 50 TD and 9 INT ever again, but when valuing his season, we need to ignore the anomalous nature of it.
This got pretty lengthy, so I'm going to table any discussions of kickoff returners and correlation coefficients for another day. There should be more than enough to chew on, here. If you're a Chiefs fan, it's easy to think that Kansas City would have been a whole lot better if they had Jay Cutler or Donovan McNabb instead of what they actually had at QB last year. But KC might have been better off if they simply had the Cleveland special teams unit instead.