Alex Smith was the punch line to a number of fantasy jokes this offseason. Now the former No. 1 overall NFL Draft choice is a legitimate waiver wire consideration thanks to his near-perfect performance in the second half of last week's loss to Houston.

Stepping in for Shaun Hill, Smith completed 15-of-22 passes for 206 yards and three touchdowns to bring San Francisco back from a 21-0 deficit. All three scores went to the team's top target, tight end Vernon Davis -- another prospective bust who is finding success this season.

Fantasy owners will no doubt be leery of jumping on Smith's bandwagon. After all, the guy has been given opportunities time and time again, only to fail. Why will this be any different?

Well, for one thing, San Francisco now has a respectable cast of receivers in place for him to throw to. With veteran Isaac Bruce, newly signed Michael Crabtree, Josh Morgan and Davis, this team could be on the cusp of a passing game explosion.

And, Smith was always in a revolving door before. This time he lost the job and had to earn it back, versus waiting for his turn in the rotation. That could mean he finally had the wake-up call he needed.

As a No. 2 fantasy quarterback, how can fantasy owners go wrong giving Smith one last chance?

Here are a few other waiver wire candidates to consider...

RB Shonn Greene, New York Jets

For Greene, injury equals opportunity. Now that Leon Washington is out with a broken fibula, the rookie back out of Iowa will assume the team's No. 2 role in the backfield behind Thomas Jones. If he continues to perform like he did last Sunday, Greene might finish the year with Jones' job. On 19 carries against Oakland the 226-pound bruising back gained 144 yards and scored two touchdowns. He doesn't have the same versatility Washington does, but Greene could serve New York as a goal line back.

WR Brian Hartline, Miami

The "other" rookie wide receiver from Ohio State had a splendid day against New Orleans, gaining 94 yards on three catches. The reason that should intrigue fantasy owners is because Miami is still a team in search of the right parts for its offense, and Hartline has the profile of a Parcells-Sparano kind-of-guy.

TE Gary Barnidge, Carolina

Who!? Barnidge, the Panthers' second-year tight end out of Louisville, caught three balls on Sunday for 77 yards. The highlight came near the start of the third quarter when he reeled in a 52-yard catch to bring Carolina near red zone territory. Barnidge's efforts went to waste in the 20-9 loss to Buffalo, and it's only fair to point out he was one of three Carolina tight ends to catch three passes in the contest.

TE Fred Davis, Washington

OK, not buying Barnidge, then how about Davis? On Monday the second-year tight end caught eight balls for 78 yards and a score in the loss to Philadelphia. Prior to that Davis had 72 yards to his name in those two seasons, and not a single score. The former USC standout was thrown to 10 times (more than primary target Santana Moss) against the Eagles and looked like a sixth-year pro. Fantasy owners should be concerned about seeing too much too soon; Davis was thrown to just once the week prior.

Here is a look at this week's buy and sell candidates:

RB Darren Sproles, San Diego

Against Kansas City, Sproles averaged 8.2 yards per carry and caught three balls for 58 yards and a score. Think those numbers are a fluke? With LaDainian Tomlinson sputtering, the Chargers need a strong presence in the backfield to keep defenses honest. Sproles is the best hope the team has, and over the next few weeks fantasy owners can expect to see him creep further into Tomlinson's workload. It's possible Sproles could be a difference-maker come fantasy playoff time.

WR Anquan Boldin, Arizona

Slowed down by a bum ankle, Boldin's numbers have been subpar (just one score), but he showed good quickness in the win over the Giants on Sunday evening (75 yards) and could be headed for a huge second half of the year. Boldin is still a legitimate No. 1 fantasy receiver, when healthy, and his asking price is currently well-below what it should be. Do the math, then make a move.

TE Jason Witten, Dallas

Witten has just 312 yards this season, and has caught just one score. But that should change in the near future now that teams will begin to show more attention to downfield threat Miles Austin. Witten rarely gets fewer than seven looks in each contest, and is as safe of a bet as any tight end in the game. By season's end he'll have 90-plus catches, more than 1,000 yards, and a half-dozen scores. It's rare that a fantasy owner would consider dealing their prized tight end, but Witten's "slow" start might actually make him available.

QB Tony Romo, Dallas

As much as we might love what Witten's future holds, we fear what's in store for Romo. Over the next seven games, Romo will face five teams ranked among the top eight in pass defense -- Eagles, Packers, Redskins, Giants, Chargers. And of the seven opponents, only one (Philadelphia) has allowed 10 or more passing scores to this point in the season. That schedule spells trouble for Romo, who was just finding his groove.

RB Larry Johnson, Kansas City

Johnson just signed his own death warrant in Kansas City, calling out coach Todd Haley and allegedly using a number of gay slurs on his Twitter account. The team is in no better shape right now with him in the lineup than without, so fantasy owners can expect Haley and the organization to take swift action with a player whose mouth has caused issues before. If you can find someone willing to buy him on the cheap, by all means do so.

WR DeSean Jackson, Philadelphia

Jackson scored twice on Monday -- a 67-yard run and a 57-yard catch. His electrifying performance will draw interest from fellow owners in your league, making now a good time to entertain offers. Jackson is one of fantasy's most inconsistent wide receivers. He is the definitive big-play receiver, but he has too many "bust" weeks to offset nights like he had on Monday. And it seems he has fallen out of favor in the Eagles passing game (rookie Jeremy Maclin has received more looks in two of the past three weeks).

Mike Beacom is a contributing writer for FootballDiehards.com.

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