Dan Arkush over at Pro Football Weekly reports that a big part of the Niners success in 09 will be their offensive line, and one player that will be watched closely is new tackle Marvel Smith. Here’s the report from their site:

49ers training-camp observers will no doubt be drawn toward Shaun Hill and Alex Smith , as they battle for the starting QB job, as well as high-profile first-round WR Michael Crabtree , who has yet to strut his stuff up to now save for an occasional sideline sprint. But another less-heralded player team insiders could be watching just as closely is ex-Steeler OLT Marvel Smith . Smith, who is being counted on to switch positions and fill a gaping hole at right tackle, has been limited up to now following his second back surgery in the last three seasons.

“Can he play, and if so, can he return to his former Pro Bowl form?” one team insider wondered aloud about the projected replacement for the departed Jonas Jennings , whose injury and character issues were a constant source of irritation. “He’s supposedly a lot more team-oriented than Jennings, who had a big ego and wouldn’t play hurt,” the insider said. “But you can’t help wondering about a 315-pound guy with back problems.”