FORT COLLINS — Jay Norvell’s CSU Rams will be without a key piece on offense and on defense for their season opener at No. 4 Texas. And the offensive piece is a big one — literally. Norvell announced during his weekly news conference Monday that 6-foot-8 tight end Jaxxon Warren, a transfer from North Texas, is out for the season after recent shoulder surgery. Warren had been expected to be a key contributor for the Rams, similar to the role served last season by former CSU tight end Dallin Holker, now with the New Orleans Saints. “Obviously, it’s a huge bummer not having one of our guys,” quarterback Brayden Fowler-Nicolosi said Monday. Norvell added that defensive lineman Nuer Gatkuoth won’t play against the Longhorns because of turf toe.