Tennessee Titans offensive tackle David Stewart underwent arthroscopic knee surgery on Thursday and is expected to miss at least two preseason games, according to Jim Wyatt of the Tennessean; Stewart suffered the injury in the team's preseason opener against the St. Louis Rams last Saturday and missed practices earlier this week.? The MRI taken revealed a cartilage tear.? Daniel Loper is expected to replace Stewart in the lineup for tonight's home game against the Oakland Raiders.? Stewart started every game last season; he signed a 6-year, $38.9 million contract extension last June.? In other Titans news? Placekicker Rob Bironas hasn't seen a football since suffering a groin injury the first week of training camp; however, that may soon change as her may start kicking a football next week.? Bironas replied when asked how long it might take to get into a groove once he returns, "That's kind of like asking what our record is going to be like at the end of the season. I'll know exactly when I get back out there. ? I wasn't expecting this, coming into camp in good shape. But it's one of those things you have to deal with." Outside linebacker David Thornton is currently out with a sore shoulder, so it appears that Stephen Tulloch will get the start against the Raiders; according to Titans head coach Jeff Fisher, "David's a little sore ? and the situation right now in Week Two of the preseason is if we have a starter who's ailing at all, it makes sense to play a younger guy.? Tully's the next one off the bench and he's had a great camp." Wide receiver Roydell Williams (ankle), cornerback Nick Harper (concussion), tight end Dwayne Blakley (groin) and linebacker Jorge Cordova (ankle) did not practice Thursday and will not play against the Raiders.?