Broncos fans can take heart, however, because when the season kicks off this weekend Denver will finally have its O-line intact and its top targets together again.
And Emmanuel Sanders is returning from a pulled right hamstring that prevented him from lining up opposite Thomas the entire preseason.
Thomas, who caught just six passes and dropped a few others in the preseason after signing a five-year, $70 million contract in July, said his game will be helped ''big time'' by Sanders' return.
''You can't double me because you have to have somebody on him, too,'' Thomas said. ''I feel like he can beat any corner man-to-man in the league. That's helping me a lot because having him on the opposite side is really big.''
Thomas said he's not cringing at the thought of Sanders returning punts, either.
''I won't be nervous,'' Thomas said. ''I know that he's going to do what he has to do.''
Same with Mathis, the 11th-year pro who signed an incentive-laden deal with Denver last month and has been cramming in the classroom and acclimating to the altitude.
''I feel really good, I've made a lot of progress each day,'' said Mathis, who blocked in a similar zone blocking scheme in Philadelphia.
Mathis said learning an entirely new playbook on the run isn't as daunting as it sounds.
''It's really not that hard. There's a lot of overlap for me, so I've seen schematically versions of everything that we do at one point in my career whether it be college or the many offenses I've played in in the pros,'' he said. ''But cramming, you sit there and you study and you learn it. If you were to count how many plays it was, it's not an outlandish number.
''Like if we're going to sit here and learn our times tables or learn 40 or 50 words in a different language, if you just study a few hours a day for a few days you're going to have it down.''
Soon, it's second nature.
''Early in my career, this would have been something that would probably be very overwhelming to me. But at this point, there's confidence and a sense of urgency just to get it done,'' Mathis said. ''I don't want them to be lax on what they expect from me. I want them to expect my best from the first snap. It doesn't matter how long I've been here. I want to be my best Game 1.''
Mathis said he's ready to play the whole game, too.
''I'd better be,'' he said. ''I feel good. Every day there's a noticeable difference in my conditioning.''
If he does get winded, however, rookie Max Garcia would spell him.
''Everything I see says he's going to be fine, but we are going to monitor him,'' coach Gary Kubiak said. ''He's told me over and over, `Coach, I'm good.' He knows himself. I'm hoping he goes the whole game and he feels good about it.''
Notes: WR Bubba Caldwell (illness) missed practice Thursday, and Kubiak was nervous the flu could spread through the locker room on the eve of the opener. ''We actually had a couple guys (feeling) brutal that pushed through it, but Bubba's pretty sick, so we sent him home,'' Kubiak said.
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