In the last couple of weeks, two teams with Super Bowl hopes -- Houston and Chicago -- have lost their starting quarterbacks. Throw in Adrian Peterson going down with an ankle injury and fantasy owners are starting to get their usual late-season headaches. Luckily, even though we're entering Week 12, the waiver wire always offers some hope. Let's take a look at this week's hot waiver wire targets and whether or not those players are worth pursuing. Jake Locker, QB, Tennessee -- Locker came in against Atlanta when starter Matt Hasselbeck left with an elbow injury. Coach Mike Munchak has already said Hasselbeck will still be the starter if he's healthy but it appears that Locker's time is coming. One thing Locker gives the Titans is mobility. Hasselbeck has been under heavy fire in recent weeks, and with his lack of mobility the veteran is a sitting duck. On Sunday, Locker was able to elude pressure and make plays down the field. One thing I noticed about Locker, though, is he really struggled throwing to his left. Damian Williams was lined up to Locker's left and he was targeted seven times. None of those seven passes ever had a chance. Every one of Locker's passes to Williams sailed over his head or out of bounds. Locker threw very well to his right and when he was on the run. I'm not sure if it was just one game or if it's an issue with mechanics but it's certainly something to keep an eye on if Locker starts this week. The Final Call: It's unlikely fantasy owners fighting for a playoff spot need a starting quarterback right now. However, if you play in a two-quarterback league Locker is worth picking up. He could have some fantasy value if Hasselbeck is sidelined. Kevin Smith, RB, Detroit -- In one of the more shocking performances in recent memory, Smith came off the street to record 201 total yards and three touchdowns Sunday against Carolina. There's no question Smith was running hard, but if you watched the game you saw how truly pathetic the Carolina run defense is right now. I can't remember a game where I've seen so many missed tackles by one team. I can say beyond a shadow of a doubt things won't get any easier for Smith this year. Now that's not to say Smith doesn't have any fantasy value. It's not like the Lions are loaded with great options at running back. Plus, Smith is a good receiver out of the backfield and the Lions love throwing the ball to their backs. Smith has obviously earned more playing time, but those big runs against Carolina will be 2-yard runs against a defense like the Chicago Bears. There's no doubt Smith benefited from a lot of poor tackling on Sunday. The Final Call: Smith is worth adding in all leagues but just temper your expectations. He has a lot more value in points per reception leagues because of his skills as a receiver. Toby Gerhart, RB, Minnesota -- Adrian Peterson went down with an ankle injury and early reports suggest that he'll miss at least one game. Gerhart is a tough call for me because I really liked him in college but so far in the NFL he's looked awful. I know he hasn't gotten a lot of opportunities but when he has run the ball he's looked slow and indecisive. Now that could change once he gets more carries, but going by what we've seen, Gerhart hasn't looked good. The one positive is we know Gerhart will catch some passes, so if you're in a points per reception league that's where a lot of his value could come. No one expects Gerhart to be Peterson but if he can catch five balls and get 70 total yards, he'll have some fantasy value. The Final Call: Gerhart is going to be a hot commodity this week but I wouldn't kill yourself trying to get him. He's obviously worth adding if you own Peterson but if you're set at running back, take a pass. Joe McKnight, RB, New York Jets -- It's been 11 weeks now so those people still supporting Shaun Greene have to face reality -- the guy simply isn't getting the job done. Greene has struggled all season, and against the Denver Broncos, McKnight gave the offense a little jolt. McKnight isn't really a 20-carry kind of running back but he's an excellent receiver and he has big-play ability, something the Jets have sorely missed from the running back position this year. Greene is expected to play on Sunday but he's still suffering from sore ribs. Throw in LaDainian Tomlinson's bad knee and it sets up for McKnight to see an increased workload against Buffalo on Sunday. The Final Call: I like what McKnight brings to the table and I think he's going to start seeing a lot more touches. I would advise getting him over someone like Gerhart for the stretch run. Riley Cooper, WR, Philadelphia -- Cooper started in place of Jeremy Maclin on Sunday and responded by catching five balls for 75 yards and a touchdown. Cooper played well against the New York Giants, and while he's certainly on the rise, Cooper's value is directly linked to Maclin's health. Once Maclin returns, Cooper is going to be battling him, DeSean Jackson, LeSean McCoy, Brent Celek and Jason Avant for targets. I think Cooper has elevated himself to the Eagles' third receiver after Sunday's performance, but it will be tough for him to remain a fantasy factor with Maclin in the lineup. To be honest, Jackson isn't much of a fantasy factor when Maclin is healthy, so it's hard to think Cooper will be any different. The Final Call: Cooper is worth adding in deeper leagues but he'll only have fantasy value if Maclin or Jackson is injured. He's more of an intriguing option for next season with Jackson likely departing. Charles Clay, TE, Miami -- I know quite a bit about Clay because I write for Inside Tulsa Sports and I followed his career in college. Clay played both running back and H-back at Tulsa but I always thought he was miscast as a running back. Clay was so productive as a receiver from the H-back position, I always questioned why the team even bothered using him in the backfield at all. It made no sense. On Sunday, Clay caught four passes for 69 yards and a score. Now, should you pick Clay up and make him your starting tight end? No, that's going a little too far. However, Clay is a guy that has a lot of upside for the rest of this season and 2012. Clay has really soft hands, so catching the ball isn't a problem. Also, because he used to play running back, Clay is a monster in the open field. I know a lot of people don't see Tulsa play every week, but trust me -- he had some of the most impressive open field runs in college football during his time there. He's still raw, but Clay has a chance to be a good NFL tight end down the road. The Final Call: Clay is worth a look if you start two tight ends, but his biggest fantasy contributions will likely come in the future. He's certainly a player to keep an eye on. You can read Thomas Casale's column ‘The Fire Sale' every Tuesday on SI.com. Also, you can follow him on Twitter or e-mail him at tcasale@mail.com for more fantasy advice.