Using ESPN standard scoring, the Bronco quarterback ties Adrian Peterson's 2007 game for the 11th best fantasy score of all time (since 2000).
In one of my leagues, with different scoring , Manning put up 65 points.
Here is the top 11, per ESPN: 1. Clinton Portis, 2003 Week 14, 54 points
2. Shaun Alexander, 2002 Week 4, 52 points
3. Doug Martin, 2012 Week 9, 51 points
4. (tie) Michael Vick, 2010 Week 10, 49 points
4. (tie) Mike Anderson, 2000 Week 14, 49 points
6. (tie) Fred Taylor, 2000 Week 12, 48 points
6. (tie) Priest Holmes, 2002 Week 12, 48 points
8. (tie) Jimmy Smith, 2000 Week 2, 47 points
8. (tie) Marshall Faulk, 2002 Week 7, 47 points
8. (tie) Jerome Harrison, 2009 Week 15, 47 points
11. (tie) Adrian Peterson, 2007 Week 9, 46 points
11. (tie) Peyton Manning, 2013 Week 1, 46 points
Right now, Manning is on pace to score 119 touchdowns this season.