http://www.coldhardfootballfacts.co...oll_Report:_the_value_of_first-round_QBs.html
Value of drafting QBs high
Here's a quick look at how draft positions relate to Super Bowl appearances:
1st Overall 7 QBs combined for 19 starts
Top 10 13 QBs, 25 starts
1st Rd 20 QBs, 36 starts
2nd Rd 4 QBs, 5 starts
3rd Rd 5 QBs, 8 starts
4th Rd 3 QBs, 4 starts
5th Rd N/A
6th Rd 4 QBs, 8 starts
7th Rd or later 2 QBs, 2 starts
Undrafted 2 QBs, 4 starts
Looking at those numbers, it's easy to see why such an onus is placed on quarterbacks drafted No. 1 overall. They account for more than one quarter of all Super Bowl starters since the merger (28.3%) and include some of the greatest names in Super Bowl history: Terry Bradshaw (4 starts, 4 wins), Troy Aikman (3/3), John Elway (5/2), Jim Plunkett (2/2), Eli Manning (2/2), Peyton Manning (2/1), Drew Bledsoe (1/0).
First-round quarterbacks, meanwhile, have made over half (53.7%) of all starts in the big game.
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It's interesting to see that, outside of the first round, the appearances are spread out rather evenly.
Sixth-round picks are just as likely to make it to the Super Bowl as second-round picks, and third rounders are even a step ahead.