This is completely untrue. His injury happened Dec 14th (week 15) against the Chargers. His arm strength and accuracy had both nose-dived well before then. Week 14 against the Bills, he threw for 0 Tds, 2 INTs and only had 173 passing yards on 14 completions. 179 yards the week before that. The Broncos were relying almost completely on the running game and their highly skilled receivers to make up for the terrible passing game that was 100% on Manning. That was happening well before the quad injury.
This makes sense if you're arguing that Manning went from healthy to not healthy in one play. That doesn't seem to be the case here, though. This appears to have been a mechanical issue, which means that he was probably feeling the negative effects long before the play that we believe he tore his quad on.
Toward the end of last season, I saw a lot of explanations stating that the issue with Manning is that his arm strength has been completely shot since his neck surgeries. Power isn't just generated in the arm: it's generated in the arm, shoulder, hips, quads, etc. So Manning's ability to generate power in his arm and shoulder was shot, he compensated by putting a heavy burden on his quads and hips. His 39 year-old body didn't hold up to the workload he subjected it to, and that was that.
According to this argument, it wasn't a freak injury, where he was fine one play and then hurt the next. It was the product of cumulative wear and tear over the course of the season, so it would show up in his performance more gradually than that, until eventually it made him pretty much useless.
Where this really gets interesting is in projecting to 2015. I'm betting that he'll feel (and look) a lot better at the start of the season, since he's had 7 months to rest up and recover. But if what I'm saying is true, he's going to be confronting the same issues again re: wear and tear, and unless he adjusts his mechanics (which it sounds like he can't, since he has to generate power from
somewhere). Which means that the likelihood of ending right back in the same situation he was in last year is pretty high.
If I'm John Elway, and I understand that this the hand I've been dealt, I make it priority #1 to upgrade the OL. A better line means that I can rely more on my ground game, so Manning doesn't have to throw so much. It also means I can better protect him, which means fewer hits (and there's a whole lot of different injuries that can further mess with his mechanics) as well as helping make sure that when he does throw his feet are planted and he isn't forced into an awkward, off-balance pass.
It remains to be seen if they intend to execute that strategy, if they can win while executing it, or even if that'll be enough to prevent Manning from getting injured again. But if they want to protect Manning, having a guy like Evan Mathis helps a lot.
Also, just as a disclaimer: I'm no expert in body mechanics or anything. I'm just basing this off of something that I read from someone who is, and it seems reasonable given what we know about Manning's past and the way he fell off last year.
