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Marvin Harrison – Peyton Manning = Keyshawn Johnson?

Posted by Chase Stuart on December 22, 2008

What would Marvin Harrison's numbers look like without Peyton Manning? Let's be clear: I don't know. You don't know. I'll never know. You'll never know. But what's the worst thing that could happen if we approach the question as logically as possible and see where it takes us?

Harrison played two seasons before Manning arrived, and they were decent enough seasons for a 1st and 2nd year wide receiver. His third year was Manning's rookie season, and Harrison played well before suffering an injury that caused him to miss four games. After that, he became Marvin Harrison™.

So how can we say how good Harrison would have been if he just had a regular old QB? For starters, let's define how good Marvin Harrison has been. Through the 2007 season, he had 1,042 receptions, 13,944 yards and 123 touchdowns. If we award 20 yards per touchdown and five yards per reception, that gives Harrison 21,614 adjusted yards in his career. Whether you love that formula or not, it gives a decent enough impression of how good Harrison has been; only Jerry Rice, Tim Brown and Cris Carter have more adjusted yards (and Harrison moved into second place this year).

The following Colts pass catchers have only played on Manning-led Colts teams: Reggie Wayne, Dallas Clark, Anthony Gonzalez, Joseph Addai and Ben Utecht; other players were so marginal that we don't care about them (I'm looking at you, Jim Finn, Ben Hartsock et al.). But while Harrison has just about only played with Peyton Manning, some other pass catchers have played with Manning and with another QB. Here's a full list, with the first column showing games played on the '98-'07 Colts and the second listing games played at any other time and place (besides 2008):

Marcus Pollard	       106	 77
Ken Dilger	        63	 93
Jerome Pathon	        46       53
Brandon Stokley	        41	 46
Troy Walters	        52	 40
Edgerrin James	        96	 32
Marshall Faulk	        16	160
Torrance Small	        16	117
Qadry Ismail	        14	110
Terrence Wilkins	41	 13
Lamont Warren	        12	 84
Dominic Rhodes	        71	  9
Tony Simmons	         6	 38
Craig Heyward	         4	145
Jermaine Wiggins	 3	104
Zack Crockett	         2	156
Ricky Proehl	         2	242

For no particularly great reason, I'm going to draw the line between Wilkins and Ismail. Warren and Rhodes were obviously running backs, and Wilkins was really just a returner during his 13-game season with the Rams. Ismail and Small basically played full seasons with the Colts and a bunch of other seasons with other teams.

That gives us nine receivers, running backs and tight ends that played with a Manning-Colts squad and a different squad. Now how the heck do we compare them?

It is obvious that a player's age must be accounted for. I looked at the top 100 pass catchers of all time and studied their drop-off rate. After smoothing out the numbers, the table below shows my results:

21	 43.6
22	 61.1
23	 75.0
24	 85.5
25	 93.0
26	 97.7
27	 99.9
28	100.0
29	 98.2
30	 94.9
31	 90.3
32	 84.8
33	 78.6
34	 72.0
35	 65.4
36	 59.0
37	 53.1
38	 48.1
39	 44.3
40	 41.8
41	 41.2
42	 39.2

In other words, the average pass catcher peaks at ages 27 and 28 -- that's when they are at 100% of their peak. At age 32, they're at 85% of their peak; at age 22, they're at 61% of their peak. Once again, you don't need to love these numbers but I think they're roughly accurate and noncontroversial. Using those numbers as a guide, we can project the number of adjusted yards for each player for each season.

Let's take Marcus Pollard as an example. At age 24, he played in 16 games. He is projected to be at 85.5% of his peak -- that gives him 13.68 adjusted games. At age 35, he played in 14 games, and we suspect he is only 65.4% of his former self; that means we'll give him 9.16 adjusted games. The table below lists all the years of Pollard's career, along with his games played * age value combination.

age	year    team    g       rec    recyd    rectd    AdjYd  Age-Game
24	1996	clt	16	 6	 86	1	 136	13.68
25	1997	clt	16	10	116	0	 166	14.87
26	1998	clt	16	24	309	4	 509	15.63
27	1999	clt	16	34	374	4	 624	15.99
28	2000	clt	16	30	439	3	 649	16.00
29	2001	clt	16	47	739	8	1134	15.72
30	2002	clt	15	43	478	6	 813	14.24
31	2003	clt	14	40	541	3	 801	12.64
32	2004	clt	13	29	309	6	 574	11.02
33	2005	det	16	46	516	3	 806	12.57
34	2006	det	15	12	100	0	 160	10.80
35	2007	sea	14	28	273	2	 453	 9.15
							6825   162.30

That 162.30 represents the number of adjusted (for age) career games he played in -- it is the sum of all of his games played per age season times the value of that age season. That number is pretty meaningless except for the fact that it can then be compared to his career adjusted yards number. He recorded 6,825 adjusted yards in his career, and accumulated 162.30 adjusted games. That means for his career, he averaged 42 adjusted yards per adjusted game. Knowing that, we can then project his whole career:

age	year    team     g      car %    proj
24	1996	clt	16	0.08	 575
25	1997	clt	16	0.09	 625
26	1998	clt	16	0.10	 657
27	1999	clt	16	0.10	 672
28	2000	clt	16	0.10	 673
29	2001	clt	16	0.10	 661
30	2002	clt	15	0.09	 599
31	2003	clt	14	0.08	 532
32	2004	clt	13	0.07	 463
33	2005	det	16	0.08	 529
34	2006	det	15	0.07	 454
35	2007	sea	14	0.06	 385
				1.00	6825

This might look complicated but it's really not that bad. First we had to see how many games Pollard played at each age, since your age is correlated to your production. Then once we total his career value of games and age, we can compare it to his actual production. Then we can put in projections for what we would guess he would have each year of his career if he was a typical receiver -- notice for his career he is still at 6,825 adjusted yards.

What's the usefulness of this? Well we can compare what we would project him to do against what he actually did. Here's a look:

year    team     act 	 proj	diff
1996	clt	 136	 575	-439
1997	clt	 166	 625	-459
1998	clt	 509	 657	-148
1999	clt	 624	 672	- 48
2000	clt	 649	 673	- 24
2001	clt	1134	 661	 473
2002	clt	 813	 599	 214
2003	clt	 801	 532	 269
2004	clt	 574	 463	 111
2005	det	 806	 529	 277
2006	det	 160	 454	-294
2007	sea	 453	 385	  68
		6825    6825       0

I've bolded the seasons where he played without Peyton Manning. For his career he outperformed his projection by 847 adjusted yards when he played with Manning and underperformed his projection by 847 yards when he didn't play with Manning. Is that mildly interesting?

Here's another way to look at it: Pollard played 38% of his adjusted career without Manning and 62% with Manning. He had 1721 adjusted yards without Manning and 5104 adjusted yards with Manning. Using those ratios, we can say that (at least according to this method of estimating) while Pollard had 6825 adjusted yards in his real career, if he played 100% of his career with Manning he'd have 8183 adjusted yards and if he played 0% of his career with Manning he'd have adjusted 4574 yards.

That's just Marcus Pollard, though. Here's how the other players have done:

	         AY car	 AY w M	 PT w M	   AY wo M  PT wo M   100% w M	100% wo M   Factor
Edgerrin James	 5567	 4839	  71%	    728	    29%	      6861	 2470	    1.78
Marcus Pollard	 6825	 5104	  62%	   1721	    38%	      8183	 4574	    0.79
Brandon Stokley	 5199	 2911	  49%	   2288	    51%	      5922	 4500	    0.32
Jerome Pathon	 4950	 2460	  43%	   2490	    57%	      5733	 4362	    0.31
Marshall Faulk	11430	 1418	  10%	  10012	    90%	     14211	11122	    0.28
Troy Walters	 1825	 1285	  59%	    540	    41%	      2192	 1305	    0.68
Torrance Small	 6952	 1046	  13%	   5906	    87%	      7851	 6814	    0.15
Qadry Ismail	 7562	  742	  11%	   6820	    89%	      6984	 7631	   -0.08
Ken Dilger	 6359	 2553	  43%	   3806	    57%	      5934	 6680	   -0.11
Average 					             63869	49457	    0.29

From left to right, those columns are adjusted yards career, adjusted yards with Manning, playing time (as a percentage of career) with Manning, adjusted yards without Manning, playing time (as a percentage of career) without Manning, the pro-rated careers if they were spent 100% with Manning, and the pro-rated careers if they were spent 100% without Manning. On average, the players would have a 29% increase in adjusted yards for their career if they spent their whole careers with Manning.

So back to Harrison. He spent the first 18% of his career (ignoring '08) without Manning and totaled 2667 adjusted yards. Over the remaining 82% of his career he had 18,947 adjusted yards; if we reduce that by 29%, he'd have 13,426 adjusted yards. That would give him 16,119 adjusted yards for his pre-2008 career. That would place him between a couple of Jets -- Don Maynard and Keyshawn Johnson -- on the career list. That's a pretty big drop.

Of course we should remember what "without Manning" means. Here it means with an average of the other QBs all the other pass catchers played with. Here's a list of the main QBs each of them played with in their non-Manning years. Judge for yourself how representative of "average" they are:

Troy Walters	    Matt Leinart
Troy Walters	    Jon Kitna
Troy Walters	    Daunte Culpepper
Torrance Small	    Jim Everett
Torrance Small	    Doug Pederson
Torrance Small	    Jim Everett
Torrance Small	    Donovan McNabb
Torrance Small	    Jim Everett
Torrance Small	    Tony Banks
Torrance Small	    Bobby Hebert
Torrance Small	    Wade Wilson
Torrance Small	    Tom Brady
Qadry Ismail	    Elvis Grbac
Qadry Ismail	    Tony Banks
Qadry Ismail	    Warren Moon
Qadry Ismail	    Tony Banks
Qadry Ismail	    Warren Moon
Qadry Ismail	    Brad Johnson
Qadry Ismail	    Jim McMahon
Marshall Faulk	    Kurt Warner
Marshall Faulk      Kurt Warner
Marshall Faulk	    Kurt Warner
Marshall Faulk      Marc Bulger
Marshall Faulk	    Marc Bulger
Marshall Faulk	    Marc Bulger
Marshall Faulk	    Marc Bulger
Marshall Faulk	    Jim Harbaugh
Marshall Faulk	    Jim Harbaugh
Marshall Faulk	    Jim Harbaugh
Marshall Faulk	    Jim Harbaugh
Marcus Pollard	    Joey Harrington
Marcus Pollard	    Matt Hasselbeck
Marcus Pollard	    Jon Kitna
Marcus Pollard	    Jim Harbaugh
Marcus Pollard	    Jim Harbaugh
Ken Dilger	    Brian Griese
Ken Dilger	    Brad Johnson
Ken Dilger	    Brad Johnson
Ken Dilger	    Jim Harbaugh
Ken Dilger	    Jim Harbaugh
Ken Dilger	    Jim Harbaugh
Jerome Pathon	    Aaron Brooks
Jerome Pathon	    Aaron Brooks
Jerome Pathon	    Aaron Brooks
Jerome Pathon	    Michael Vick
Edgerrin James	    Matt Leinart
Edgerrin James	    Kurt Warner
Brandon Stokley	    Jay Cutler
Brandon Stokley	    Jeff Blake
Brandon Stokley	    Elvis Grbac
Brandon Stokley	    Tony Banks
Brandon Stokley	    Tony Banks

So what do you think? With Peyton Manning, Harrison's career stats make him one of the top three or four receivers in modern history. Without Peyton Manning, is he just one of the top three or four WRs from his draft class?

This entry was posted on Monday, December 22nd, 2008 at 10:41 pm and is filed under History, Insane ideas, Statgeekery. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.